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Image sensor format
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In digital photography, the image sensor format is the shape and size of the image sensor.
The image sensor format of a digital camera determines the angle of view of a particular lens when used with a particular sensor. Because the image sensors in many digital cameras are smaller than the 24 mm × 36 mm image area of full-frame 35 mm cameras, a lens of a given focal length gives a narrower field of view in such cameras.
Sensor size is often expressed as optical format in inches. Other measures are also used; see table of sensor formats and sizes below.
Lenses produced for 35 mm film cameras may mount well on the digital bodies, but the larger image circle of the 35 mm system lens allows unwanted light into the camera body, and the smaller size of the image sensor compared to 35 mm film format results in cropping of the image. This latter effect is known as field-of-view crop. The format size ratio (relative to the 35 mm film format) is known as the field-of-view crop factor, crop factor, lens factor, focal-length conversion factor, focal-length multiplier, or lens multiplier.
Sensor size and depth of field
[edit]Three possible depth-of-field comparisons between formats are discussed, applying the formulae derived in the article on depth of field. The depths of field of the three cameras may be the same, or different in either order, depending on what is held constant in the comparison.
Considering a picture with the same subject distance and angle of view for two different formats:
so the DOFs are in inverse proportion to the absolute aperture diameters and .
Using the same absolute aperture diameter for both formats with the "same picture" criterion (equal angle of view, magnified to same final size) yields the same depth of field. It is equivalent to adjusting the f-number inversely in proportion to crop factor – a smaller f-number for smaller sensors (this also means that, when holding the shutter speed fixed, the exposure is changed by the adjustment of the f-number required to equalise depth of field. But the aperture area is held constant, so sensors of all sizes receive the same total amount of light energy from the subject. The smaller sensor is then operating at a lower ISO setting, by the square of the crop factor). This condition of equal field of view, equal depth of field, equal aperture diameter, and equal exposure time is known as "equivalence".[1]
And, we might compare the depth of field of sensors receiving the same photometric exposure – the f-number is fixed instead of the aperture diameter – the sensors are operating at the same ISO setting in that case, but the smaller sensor is receiving less total light, by the area ratio. The ratio of depths of field is then
where and are the characteristic dimensions of the format, and thus is the relative crop factor between the sensors. It is this result that gives rise to the common opinion that small sensors yield greater depth of field than large ones.
An alternative is to consider the depth of field given by the same lens in conjunction with different sized sensors (changing the angle of view). The change in depth of field is brought about by the requirement for a different degree of enlargement to achieve the same final image size. In this case the ratio of depths of field becomes
- .
In practice, if applying a lens with a fixed focal length and a fixed aperture and made for an image circle to meet the requirements for a large sensor is to be adapted, without changing its physical properties, to smaller sensor sizes neither the depth of field nor the light gathering will change.
Sensor size, noise and dynamic range
[edit]Discounting photo response non-uniformity (PRNU) and dark noise variation, which are not intrinsically sensor-size dependent, the noises in an image sensor are shot noise, read noise, and dark noise. The overall signal to noise ratio of a sensor (SNR), expressed as signal electrons relative to rms noise in electrons, observed at the scale of a single pixel, assuming shot noise from Poisson distribution of signal electrons and dark electrons, is
where is the incident photon flux (photons per second in the area of a pixel), is the quantum efficiency, is the exposure time, is the pixel dark current in electrons per second and is the pixel read noise in electrons rms.[2]
Each of these noises has a different dependency on sensor size.
Exposure and photon flux
[edit]Image sensor noise can be compared across formats for a given fixed photon flux per pixel area (the P in the formulas); this analysis is useful for a fixed number of pixels with pixel area proportional to sensor area, and fixed absolute aperture diameter for a fixed imaging situation in terms of depth of field, diffraction limit at the subject, etc. Or it can be compared for a fixed focal-plane illuminance, corresponding to a fixed f-number, in which case P is proportional to pixel area, independent of sensor area. The formulas above and below can be evaluated for either case.
Shot noise
[edit]In the above equation, the shot noise SNR is given by
- .
Apart from the quantum efficiency it depends on the incident photon flux and the exposure time, which is equivalent to the exposure and the sensor area; since the exposure is the integration time multiplied with the image plane illuminance, and illuminance is the luminous flux per unit area. Thus for equal exposures, the signal to noise ratios of two different size sensors of equal quantum efficiency and pixel count will (for a given final image size) be in proportion to the square root of the sensor area (or the linear scale factor of the sensor). If the exposure is constrained by the need to achieve some required depth of field (with the same shutter speed) then the exposures will be in inverse relation to the sensor area, producing the interesting result that if depth of field is a constraint, image shot noise is not dependent on sensor area. For identical f-number lenses the signal to noise ratio increases as square root of the pixel area, or linearly with pixel pitch. As typical f-numbers for lenses for cell phones and DSLR are in the same range f/1.5–2 it is interesting to compare performance of cameras with small and big sensors. A good 2018 cell phone camera with a typical pixel size of 1.1 μm (Samsung A8) would have about 3 times worse SNR due to shot noise than a 3.7 μm pixel interchangeable lens camera (Panasonic G85) and 5 times worse than a 6 μm full frame camera (Sony A7 III). Taking into consideration the dynamic range makes the difference even more prominent. As such the trend of increasing the number of "megapixels" in cell phone cameras during last 10 years was caused rather by marketing strategy to sell "more megapixels" than by attempts to improve image quality.
Read noise
[edit]The read noise is the total of all the electronic noises in the conversion chain for the pixels in the sensor array. To compare it with photon noise, it must be referred back to its equivalent in photoelectrons, which requires the division of the noise measured in volts by the conversion gain of the pixel. This is given, for an active pixel sensor, by the voltage at the input (gate) of the read transistor divided by the charge which generates that voltage, . This is the inverse of the capacitance of the read transistor gate (and the attached floating diffusion) since capacitance .[3] Thus .
In general for a planar structure such as a pixel, capacitance is proportional to area, therefore the read noise scales down with sensor area, as long as pixel area scales with sensor area, and that scaling is performed by uniformly scaling the pixel.
Considering the signal to noise ratio due to read noise at a given exposure, the signal will scale as the sensor area along with the read noise and therefore read noise SNR will be unaffected by sensor area. In a depth of field constrained situation, the exposure of the larger sensor will be reduced in proportion to the sensor area, and therefore the read noise SNR will reduce likewise.
Dark noise
[edit]Dark current contributes two kinds of noise: dark offset, which is only partly correlated between pixels, and the shot noise associated with dark offset, which is uncorrelated between pixels. Only the shot-noise component Dt is included in the formula above, since the uncorrelated part of the dark offset is hard to predict, and the correlated or mean part is relatively easy to subtract off. The mean dark current contains contributions proportional both to the area and the linear dimension of the photodiode, with the relative proportions and scale factors depending on the design of the photodiode.[4] Thus in general the dark noise of a sensor may be expected to rise as the size of the sensor increases. However, in most sensors the mean pixel dark current at normal temperatures is small, lower than 50 e- per second,[5] thus for typical photographic exposure times dark current and its associated noises may be discounted. At very long exposure times, however, it may be a limiting factor. And even at short or medium exposure times, a few outliers in the dark-current distribution may show up as "hot pixels". Typically, for astrophotography applications sensors are cooled to reduce dark current in situations where exposures may be measured in several hundreds of seconds.
Dynamic range
[edit]Dynamic range is the ratio of the largest and smallest recordable signal, the smallest being typically defined by the 'noise floor'. In the image sensor literature, the noise floor is taken as the readout noise, so [6] (note, the read noise is the same quantity as referred to in the SNR calculation[2]).
Sensor size and diffraction
[edit]The resolution of all optical systems is limited by diffraction. One way of considering the effect that diffraction has on cameras using different sized sensors is to consider the modulation transfer function (MTF). Diffraction is one of the factors that contribute to the overall system MTF. Other factors are typically the MTFs of the lens, anti-aliasing filter and sensor sampling window.[7] The spatial cut-off frequency due to diffraction through a lens aperture is
where λ is the wavelength of the light passing through the system and N is the f-number of the lens. If that aperture is circular, as are (approximately) most photographic apertures, then the MTF is given by
for and for [8] The diffraction based factor of the system MTF will therefore scale according to and in turn according to (for the same light wavelength).
In considering the effect of sensor size, and its effect on the final image, the different magnification required to obtain the same size image for viewing must be accounted for, resulting in an additional scale factor of where is the relative crop factor, making the overall scale factor . Considering the three cases above:
For the 'same picture' conditions, same angle of view, subject distance and depth of field, then the f-numbers are in the ratio , so the scale factor for the diffraction MTF is 1, leading to the conclusion that the diffraction MTF at a given depth of field is independent of sensor size.
In both the 'same photometric exposure' and 'same lens' conditions, the f-number is not changed, and thus the spatial cutoff and resultant MTF on the sensor is unchanged, leaving the MTF in the viewed image to be scaled as the magnification, or inversely as the crop factor.
Sensor format and lens size
[edit]It might be expected that lenses appropriate for a range of sensor sizes could be produced by simply scaling the same designs in proportion to the crop factor.[9] Such an exercise would in theory produce a lens with the same f-number and angle of view, with a size proportional to the sensor crop factor. In practice, simple scaling of lens designs is not always achievable, due to factors such as the non-scalability of manufacturing tolerance, structural integrity of glass lenses of different sizes and available manufacturing techniques and costs. Moreover, to maintain the same absolute amount of information in an image (which can be measured as the space-bandwidth product[10]) the lens for a smaller sensor requires a greater resolving power. The development of the 'Tessar' lens is discussed by Nasse,[11] and shows its transformation from an f/6.3 lens for plate cameras using the original three-group configuration through to an f/2.8 5.2 mm four-element optic with eight extremely aspheric surfaces, economically manufacturable because of its small size. Its performance is 'better than the best 35 mm lenses – but only for a very small image'.
In summary, as sensor size reduces, the accompanying lens designs will change, often quite radically, to take advantage of manufacturing techniques made available due to the reduced size. The functionality of such lenses can also take advantage of these, with extreme zoom ranges becoming possible. These lenses are often very large in relation to sensor size, but with a small sensor can be fitted into a compact package.
Small body means small lens and means small sensor, so to keep smartphones slim and light, the smartphone manufacturers use a tiny sensor usually less than the 1/2.3" used in most bridge cameras. At one time only Nokia 808 PureView used a 1/1.2" sensor, almost twice the size of a 1/2.3" sensor. Bigger sensors have the advantage of better image quality, but with improvements in sensor technology, smaller sensors can achieve the feats of earlier larger sensors. These improvements in sensor technology allow smartphone manufacturers to use image sensors as small as 1/4" without sacrificing too much image quality compared to budget point & shoot cameras.[12]
Active area of the sensor
[edit]For calculating camera angle of view one should use the size of active area of the sensor. Active area of the sensor implies an area of the sensor on which image is formed in a given mode of the camera. The active area may be smaller than the image sensor, and active area can differ in different modes of operation of the same camera. Active area size depends on the aspect ratio of the sensor and aspect ratio of the output image of the camera. The active area size can depend on number of pixels in given mode of the camera. The active area size and lens focal length determines angles of view.[13]
Sensor size and shading effects
[edit]Semiconductor image sensors can suffer from shading effects at large apertures and at the periphery of the image field, due to the geometry of the light cone projected from the exit pupil of the lens to a point, or pixel, on the sensor surface. The effects are discussed in detail by Catrysse and Wandell.[14] In the context of this discussion the most important result from the above is that to ensure a full transfer of light energy between two coupled optical systems such as the lens' exit pupil to a pixel's photoreceptor the geometrical extent (also known as etendue or light throughput) of the objective lens / pixel system must be smaller than or equal to the geometrical extent of the microlens / photoreceptor system. The geometrical extent of the objective lens / pixel system is given by where wpixel is the width of the pixel and (f/#)objective is the f-number of the objective lens. The geometrical extent of the microlens / photoreceptor system is given by where wphotoreceptor is the width of the photoreceptor and (f/#)microlens is the f-number of the microlens.
In order to avoid shading, therefore
If wphotoreceptor / wpixel = ff, the linear fill factor of the lens, then the condition becomes
Thus if shading is to be avoided the f-number of the microlens must be smaller than the f-number of the taking lens by at least a factor equal to the linear fill factor of the pixel. The f-number of the microlens is determined ultimately by the width of the pixel and its height above the silicon, which determines its focal length. In turn, this is determined by the height of the metallisation layers, also known as the 'stack height'. For a given stack height, the f-number of the microlenses will increase as pixel size reduces, and thus the objective lens f-number at which shading occurs will tend to increase.[a]
In order to maintain pixel counts smaller sensors will tend to have smaller pixels, while at the same time smaller objective lens f-numbers are required to maximise the amount of light projected on the sensor. To combat the effect discussed above, smaller format pixels include engineering design features to allow the reduction in f-number of their microlenses. These may include simplified pixel designs which require less metallisation, 'light pipes' built within the pixel to bring its apparent surface closer to the microlens and 'back side illumination' in which the wafer is thinned to expose the rear of the photodetectors and the microlens layer is placed directly on that surface, rather than the front side with its wiring layers.[b]
Common image sensor formats
[edit]
For interchangeable-lens cameras
[edit]Some professional DSLRs, SLTs and mirrorless cameras use full-frame sensors, equivalent to the size of a frame of 35 mm film.
Most consumer-level DSLRs, SLTs and mirrorless cameras use relatively large sensors, either somewhat under the size of a frame of APS-C film, with a crop factor of 1.5–1.6; or 30% smaller than that, with a crop factor of 2.0 (this is the Four Thirds System, adopted by OM System (formerly Olympus) and Panasonic).
As of November 2013[update], there was only one mirrorless model equipped with a very small sensor, more typical of compact cameras: the Pentax Q7, with a 1/1.7" sensor (4.55 crop factor). See section § Smaller sensors below.
Many different terms are used in marketing to describe DSLR/SLT/mirrorless sensor formats, including the following:
- 860 mm2 area Full-frame digital SLR format, with sensor dimensions nearly equal to those of 35 mm film (36×24 mm) from Pentax, Panasonic, Leica, Nikon, Canon, Sony and Sigma.
- 370 mm2 area APS-C standard format from Nikon, Pentax, Sony, Fujifilm, Sigma (crop factor 1.5) (actual APS-C film is bigger, however)
- 330 mm2 area APS-C smaller format from Canon (crop factor 1.6)
- 225 mm2 area Micro Four Thirds System format from Panasonic, OM System, Blackmagic Design, and Polaroid (crop factor 2.0)
Obsolescent and out-of-production sensor sizes include:
- 548 mm2 area Leica's M8 and M8.2 sensor (crop factor 1.33). Current M-series sensors are effectively full-frame (crop factor 1.0).
- 548 mm2 area Canon's APS-H format for high-speed pro-level DSLRs (crop factor 1.3). Current 1D/5D-series sensors are effectively full-frame (crop factor 1.0).
- 548 mm2 area APS-H format for the high-end mirrorless SD Quattro H from Sigma (crop factor 1.35)
- 370 mm2 area APS-C crop factor 1.5 format from Epson, Samsung NX, Konica Minolta.
- 286 mm2 area Foveon X3 format used in Sigma SD-series DSLRs and DP-series mirrorless (crop factor 1.7). Later models such as the SD1, DP2 Merrill and most of the Quattro series use a crop factor 1.5 Foveon sensor; the even more recent Quattro H mirrorless uses an APS-H Foveon sensor with a 1.35 crop factor.
- 225 mm2 area Four Thirds System format from Olympus (crop factor 2.0)
- 116 mm2 area 1" Nikon CX format used in Nikon 1 series[17] and Samsung mini-NX series (crop factor 2.7)
- 43 mm2 area 1/1.7" Pentax Q7 (4.55 crop factor)
- 30 mm2 area 1/2.3" original Pentax Q (5.6 crop factor). Current Q-series cameras have a crop factor of 4.55.
When full-frame sensors were first introduced, production costs could exceed twenty times the cost of an APS-C sensor. Only twenty full-frame sensors can be produced on an 8 inches (20 cm) silicon wafer, which would fit 100 or more APS-C sensors, and there is a significant reduction in yield due to the large area for contaminants per component. Additionally, full frame sensor fabrication originally required three separate exposures during each step of the photolithography process, which requires separate masks and quality control steps. Canon selected the intermediate APS-H size, since it was at the time the largest that could be patterned with a single mask, helping to control production costs and manage yields.[18] Newer photolithography equipment now allows single-pass exposures for full-frame sensors, although other size-related production constraints remain much the same.
Due to the ever-changing constraints of semiconductor fabrication and processing, and because camera manufacturers often source sensors from third-party foundries, it is common for sensor dimensions to vary slightly within the same nominal format. For example, the Nikon D3 and D700 cameras' nominally full-frame sensors actually measure 36 × 23.9 mm, slightly smaller than a 36 × 24 mm frame of 35 mm film. As another example, the Pentax K200D's sensor (made by Sony) measures 23.5 × 15.7 mm, while the contemporaneous K20D's sensor (made by Samsung) measures 23.4 × 15.6 mm.
Most of these image sensor formats approximate the 3:2 aspect ratio of 35 mm film. Again, the Four Thirds System is a notable exception, with an aspect ratio of 4:3 as seen in most compact digital cameras (see below).
Smaller sensors
[edit]Most sensors are made for camera phones, compact digital cameras, and bridge cameras. Most image sensors equipping compact cameras have an aspect ratio of 4:3. This matches the aspect ratio of the popular SVGA, XGA, and SXGA display resolutions at the time of the first digital cameras, allowing images to be displayed on usual monitors without cropping.
As of December 2010[update] most compact digital cameras used small 1/2.3" sensors. Such cameras include Canon PowerShot SX230 IS, Fujifilm Finepix Z90 and Nikon Coolpix S9100. Some older digital cameras (mostly from 2005–2010) used even smaller 1/2.5" sensors: these include Panasonic Lumix DMC-FS62, Canon PowerShot SX120 IS, Sony Cyber-shot DSC-S700, and Casio Exilim EX-Z80.
As of 2018 high-end compact cameras using one inch sensors that have nearly four times the area of those equipping common compacts include Canon PowerShot G-series (G3 X to G9 X), Sony DSC-RX100 series, Panasonic Lumix DC-TZ200 and Panasonic DMC-LX15. Canon has an APS-C sensor on its top model PowerShot G1 X Mark III.

Finally, Sony has the DSC-RX1 and DSC-RX1R cameras in their lineup, which have a full-frame sensor usually only used in professional DSLRs, SLTs and MILCs.
Due to the size constraints of powerful zoom objectives, most current bridge cameras have 1/2.3" sensors, as small as those used in common more compact cameras. As lens sizes are proportional to the image sensor size, smaller sensors enable large zoom amounts with moderate size lenses. In 2011 the high-end Fujifilm X-S1 was equipped with a much larger 2/3" sensor. In 2013–2014, both Sony (Cyber-shot DSC-RX10) and Panasonic (Lumix DMC-FZ1000) produced bridge cameras with 1" sensors.
Since the 2020s sensors of many camera phones has surpassed the size of typical compact cameras. The iPhone 13 released in 2021 has a main camera sensor size of 1/1.9".[19] The Nokia N8 (2010)'s 1/1.83" sensor was the largest in a phone in late 2011. The Nokia 808 (2012) surpasses compact cameras with its 41 million pixels, 1/1.2" sensor.[20] Sensor sizes of 1/2.3" and smaller are common in webcams, digital camcorders and most other small devices.
Medium-format digital sensors
[edit]The largest digital sensors in commercially available cameras are described as "medium format", in reference to film formats of similar dimensions. Although the most common medium format film, the 120 roll, is 6 cm (2.4 in) wide, and is most commonly shot square, the most common "medium-format" digital sensor sizes are approximately 48 mm × 36 mm (1.9 in × 1.4 in), which is roughly twice the size of a full-frame DSLR sensor format.
Available CCD sensors include Phase One's P65+ digital back with Dalsa's 53.9 mm × 40.4 mm (2.12 in × 1.59 in) sensor containing 60.5 megapixels[21] and Leica's "S-System" DSLR with a 45 mm × 30 mm (1.8 in × 1.2 in) sensor containing 37-megapixels.[22] In 2010, Pentax released the 40MP 645D medium format DSLR with a 44 mm × 33 mm (1.7 in × 1.3 in) CCD sensor;[23] later models of the 645 series kept the same sensor size but replaced the CCD with a CMOS sensor. In 2016, Hasselblad announced the X1D, a 50MP medium-format mirrorless camera, with a 44 mm × 33 mm (1.7 in × 1.3 in) CMOS sensor.[24] In late 2016, Fujifilm also announced its new Fujifilm GFX 50S medium format, mirrorless entry into the market, with a 43.8 mm × 32.9 mm (1.72 in × 1.30 in) CMOS sensor and 51.4MP. [25] [26]
Table of sensor formats and sizes
[edit]
Sensor sizes are expressed in inches notation because at the time of the popularization of digital image sensors they were used to replace video camera tubes. The common 1" outside diameter circular video camera tubes have a rectangular photo sensitive area about 16 mm on the diagonal, so a digital sensor with a 16 mm diagonal size is a 1" video tube equivalent. The name of a 1" digital sensor should more accurately be read as "one inch video camera tube equivalent" sensor. Current digital image sensor size descriptors are the video camera tube equivalency size, not the actual size of the sensor. For example, a 1" sensor has a diagonal measurement of 16 mm.[27][28]

Sizes are often expressed as a fraction of an inch, with a one in the numerator, and a decimal number in the denominator. For example, 1/2.5 converts to 2/5 as a simple fraction, or 0.4 as a decimal number. This "inch" system gives a result approximately 1.5 times the length of the diagonal of the sensor. This "optical format" measure goes back to the way image sizes of video cameras used until the late 1980s were expressed, referring to the outside diameter of the glass envelope of the video camera tube. David Pogue of The New York Times states that "the actual sensor size is much smaller than what the camera companies publish – about one-third smaller." For example, a camera advertising a 1/2.7" sensor does not have a sensor with a diagonal of 0.37 in (9.4 mm); instead, the diagonal is closer to 0.26 in (6.6 mm).[29][30][31] Instead of "formats", these sensor sizes are often called types, as in "1/2-inch-type CCD."
Due to inch-based sensor formats not being standardized, their exact dimensions may vary, but those listed are typical.[30] The listed sensor areas span more than a factor of 1000 and are proportional to the maximum possible collection of light and image resolution (same lens speed, i.e., minimum f-number), but in practice are not directly proportional to image noise or resolution due to other limitations. See comparisons.[32][33] Film format sizes are also included, for comparison. The application examples of phone or camera may not show the exact sensor sizes.
| Type | Diagonal (mm) | Width (mm) | Height (mm) | Aspect Ratio | Area (mm2) | Stops (area)[A] | Crop factor[B] |
|---|---|---|---|---|---|---|---|
| 1/10" | 1.60 | 1.28 | 0.96 | 4:3 | 1.23 | −9.46 | 27.04 |
| 1/8" (Sony DCR-SR68, DCR-DVD110E) | 2.00 | 1.60 | 1.20 | 4:3 | 1.92 | −8.81 | 21.65 |
| 1/6" (Panasonic SDR-H20, SDR-H200) | 3.00 | 2.40 | 1.80 | 4:3 | 4.32 | −7.64 | 14.14 |
| 1/4"[34] | 4.50 | 3.60 | 2.70 | 4:3 | 9.72 | −6.47 | 10.81 |
| 1/3.6" (Nokia Lumia 720)[35] | 5.00 | 4.00 | 3.00 | 4:3 | 12.0 | −6.17 | 8.65 |
| 1/3.2" (iPhone 5)[36] | 5.68 | 4.54 | 3.42 | 4:3 | 15.50 | −5.80 | 7.61 |
| 1/3.09" Sony EXMOR IMX351[37] | 5.82 | 4.66 | 3.5 | 4:3 | 16.3 | −5.73 | 7.43 |
| Standard 8 mm film frame | 5.94 | 4.8 | 3.5 | 11:8 | 16.8 | −5.68 | 7.28 |
| 1/3" (iPhone 5S, iPhone 6, LG G3[38]) | 6.00 | 4.80 | 3.60 | 4:3 | 17.30 | −5.64 | 7.21 |
| 1/2.9" Sony EXMOR IMX322[39] | 6.23 | 4.98 | 3.74 | 4:3 | 18.63 | −5.54 | 6.92 |
| 1/2.7" Fujifilm 2800 Zoom | 6.72 | 5.37 | 4.04 | 4:3 | 21.70 | −5.32 | 6.44 |
| Super 8 mm film frame | 7.04 | 5.79 | 4.01 | 13:9 | 23.22 | −5.22 | 6.15 |
| 1/2.5" (Nokia Lumia 1520, Sony Cyber-shot DSC-T5, iPhone XS[40]) | 7.18 | 5.76 | 4.29 | 4:3 | 24.70 | −5.13 | 6.02 |
| 1/2.3" (Pentax Q, Sony Cyber-shot DSC-W330, GoPro HERO3, Panasonic HX-A500, Google Pixel/Pixel+, DJI Phantom 3[41]/Mavic 2 Zoom[42]), Nikon P1000/P900 | 7.66 | 6.17 | 4.55 | 4:3 | 28.50 | −4.94 | 5.64 |
| 1/2.3" Sony Exmor IMX220[43] | 7.87 | 6.30 | 4.72 | 4:3 | 29.73 | −4.86 | 5.49 |
| 1/2" (Fujifilm HS30EXR, Xiaomi Mi 9, OnePlus 7, Espros EPC 660, DJI Mavic Air 2) | 8.00 | 6.40 | 4.80 | 4:3 | 30.70 | −4.81 | 5.41 |
| 1/1.8" (Nokia N8) (Olympus C-5050, C-5060, C-7070) | 8.93 | 7.18 | 5.32 | 4:3 | 38.20 | −4.50 | 4.84 |
| 1/1.7" (Pentax Q7, Canon G10, G15, Huawei P20 Pro, Huawei P30 Pro, Huawei Mate 20 Pro) | 9.50 | 7.60 | 5.70 | 4:3 | 43.30 | −4.32 | 4.55 |
| 1/1.6" (Fujifilm F200EXR[44]) | 10.07 | 8.08 | 6.01 | 4:3 | 48.56 | −4.15 | 4.30 |
| 2/3" (Nokia Lumia 1020, Fujifilm X10, X20, XF1) | 11.00 | 8.80 | 6.60 | 4:3 | 58.10 | −3.89 | 3.93 |
| 1/1.33" (Samsung Galaxy S20 Ultra)[45] | 12 | 9.6 | 7.2 | 4:3 | 69.12 | −3.64 | 3.58 |
| Standard 16 mm film frame | 12.70 | 10.26 | 7.49 | 11:8 | 76.85 | −3.49 | 3.41 |
| 1/1.2" (Nokia 808 PureView) | 13.33 | 10.67 | 8.00 | 4:3 | 85.33 | −3.34 | 3.24 |
| 1/1.12" (Xiaomi Mi 11 Ultra) | 14.29 | 11.43 | 8.57 | 4:3 | 97.96 | 3.03 | |
| Blackmagic Pocket Cinema Camera & Blackmagic Studio Camera | 14.32 | 12.48 | 7.02 | 16:9 | 87.6 | −3.30 | 3.02 |
| Super 16 mm film frame | 14.54 | 12.52 | 7.41 | 5:3 | 92.80 | −3.22 | 2.97 |
| 1" (Nikon CX, Sony RX100, Sony RX10, Sony ZV-1, Samsung NX Mini) | 15.86 | 13.20 | 8.80 | 3:2 | 116 | −2.89 | 2.72 |
| 1" Digital Bolex d16 | 16.00 | 12.80 | 9.60 | 4:3 | 123 | −2.81 | 2.70 |
| 1" Kodak DCS-200 | 16.81 | 14.00 | 9.30 | 3:2 | 130.2 | −2.73 | 2.57 |
| 1.1" Sony IMX253[46] | 17.46 | 14.10 | 10.30 | 11:8 | 145 | −2.57 | 2.47 |
| Blackmagic Cinema Camera EF | 18.13 | 15.81 | 8.88 | 16:9 | 140 | −2.62 | 2.38 |
| Blackmagic Pocket Cinema Camera 4K | 21.44 | 18.96 | 10 | 19:10 | 190 | −2.19 | 2.01 |
| Four Thirds, Micro Four Thirds ("4/3", "m4/3") | 21.60 | 17.30 | 13 | 4:3 | 225 | −1.94 | 2.00 |
| Blackmagic Production Camera/URSA/URSA Mini 4K | 24.23 | 21.12 | 11.88 | 16:9 | 251 | −1.78 | 1.79 |
| 1.5" Canon PowerShot G1 X Mark II | 23.36 | 18.70 | 14 | 4:3 | 262 | −1.72 | 1.85 |
| "35mm" 2 Perf Techniscope | 23.85 | 21.95 | 9.35 | 7:3 | 205.23 | −2.07 | 1.81 |
| original Sigma Foveon X3 | 24.90 | 20.70 | 13.80 | 3:2 | 286 | −1.60 | 1.74 |
| RED DRAGON 4.5K (RAVEN) | 25.50 | 23.00 | 10.80 | 19:9 | 248.4 | −1.80 | 1.66 |
| "Super 35mm" 2 Perf | 26.58 | 24.89 | 9.35 | 8:3 | 232.7 | −1.89 | 1.62 |
| Canon EF-S, APS-C | 26.82 | 22.30 | 14.90 | 3:2 | 332 | −1.38 | 1.61 |
| Standard 35 mm film frame (movie) | 27.20 | 22.0 | 16.0 | 11:8 | 352 | −1.30 | 1.59 |
| Blackmagic URSA Mini/Pro 4.6K | 29 | 25.34 | 14.25 | 16:9 | 361 | −1.26 | 1.49 |
| APS-C (Sony α, Sony E, Nikon DX, Pentax K, Samsung NX, Fuji X) | 28.2–28.4 | 23.6–23.7 | 15.60 | 3:2 | 368–370 | −1.23 to −1.22 | 1.52–1.54 |
| Super 35 mm film 3 perf | 28.48 | 24.89 | 13.86 | 9:5 | 344.97 | −1.32 | 1.51 |
| RED DRAGON 5K S35 | 28.9 | 25.6 | 13.5 | 17:9 | 345.6 | −1.32 | 1.49 |
| Super 35mm film 4 perf | 31.11 | 24.89 | 18.66 | 4:3 | 464 | −0.90 | 1.39 |
| Canon APS-H | 33.50 | 27.90 | 18.60 | 3:2 | 519 | −0.74 | 1.29 |
| ARRI ALEV III (ALEXA SXT, ALEXA MINI, AMIRA), RED HELIUM 8K S35 | 33.80 | 29.90 | 15.77 | 17:9 | 471.52 | −0.87 | 1.28 |
| RED DRAGON 6K S35 | 34.50 | 30.7 | 15.8 | 35:18 | 485.06 | −0.83 | 1.25 |
| 35 mm film full-frame | 43.1–43.3 | 35.8–36 | 23.9–24 | 3:2 | 856–864 | 0 | 1.0 |
| ARRI ALEXA LF | 44.71 | 36.70 | 25.54 | 13:9 | 937.32 | 0.12 | 0.96 |
| RED Dragon/Monstro/V-Raptor 8K VV, Panavision Millenium DXL/DXL2 | 46.31 | 40.96 | 21.60 | 17:9 | 884.74 | 0.03 | 0.93 |
| Leica S | 54 | 45 | 30 | 3:2 | 1350 | 0.64 | 0.80 |
| Pentax 645D, Hasselblad X1D-50c, Hasselblad H6D-50c, CFV-50c, Fujifilm GFX 50S[47][48] | 55 | 43.8 | 32.9 | 4:3 | 1452 | 0.75 | 0.79 |
| Standard 65/70 mm film frame | 57.30 | 52.48 | 23.01 | 7:3 | 1208 | 0.48 | 0.76 |
| ARRI ALEXA 65 | 59.86 | 54.12 | 25.58 | 19:9 | 1384.39 | 0.68 | 0.72 |
| Kodak KAF 39000 CCD[49] | 61.30 | 49 | 36.80 | 4:3 | 1803 | 1.06 | 0.71 |
| Leaf AFi 10 | 66.57 | 56 | 36 | 14:9 | 2016 | 1.22 | 0.65 |
| Medium-format (Hasselblad H5D-60c, Hasselblad H6D-100c)[50] | 67.08 | 53.7 | 40.2 | 4:3 | 2159 | 1.32 | 0.65 |
| Phase One P 65+, IQ160, IQ180 | 67.40 | 53.90 | 40.40 | 4:3 | 2178 | 1.33 | 0.64 |
| Medium-format 6×4.5 cm (also called 645 format) | 70 | 42 | 56 | 3:4 | 2352 | 1.44 | 0.614 |
| Medium-format 6×6 cm | 79 | 56 | 56 | 1:1 | 3136 | 1.86 | 0.538 |
| IMAX film frame | 87.91 | 70.41 | 52.63 | 4:3 | 3706 | 2.10 | 0.49 |
| Medium-format 6×7 cm | 89.6 | 70 | 56 | 5:4 | 3920 | 2.18 | 0.469 |
| Medium-format 6×8 cm | 94.4 | 76 | 56 | 3:4 | 4256 | 2.30 | 0.458 |
| Medium-format 6×9 cm | 101 | 84 | 56 | 3:2 | 4704 | 2.44 | 0.43 |
| Large-format film 4×5 inch | 150 | 121 | 97 | 5:4 | 11737 | 3.76 | 0.29 |
| Large-format film 5×7 inch | 210 | 178 | 127 | 7:5 | 22606 | 4.71 | 0.238 |
| Large-format film 8×10 inch | 300 | 254 | 203 | 5:4 | 51562 | 5.90 | 0.143 |
See also
[edit]Notes
[edit]Footnotes and references
[edit]- ^ "What is equivalence and why should I care?". DP Review. 2014-07-07. Retrieved 2017-05-03.
- ^ a b Fellers, Thomas J.; Davidson, Michael W. "CCD Noise Sources and Signal-to-Noise Ratio". Hamamatsu Corporation. Retrieved 20 November 2013.
- ^ Aptina Imaging Corporation. "Leveraging Dynamic Response Pixel Technology to Optimize Inter-scene Dynamic Range" (PDF). Aptina Imaging Corporation. Retrieved 17 December 2011.
- ^ Loukianova, Natalia V.; Folkerts, Hein Otto; Maas, Joris P. V.; Verbugt, Joris P. V.; Daniël W. E. Mierop, Adri J.; Hoekstra, Willem; Roks, Edwin and Theuwissen, Albert J. P. (January 2003). "Leakage Current Modeling of Test Structures for Characterization of Dark Current in CMOS Image Sensors" (PDF). IEEE Transactions on Electron Devices. 50 (1): 77–83. Bibcode:2003ITED...50...77L. doi:10.1109/TED.2002.807249. Retrieved 17 December 2011.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ "Dark Count". Apogee Imaging Systems. Retrieved 17 December 2011.
- ^ Kavusi, Sam; El Gamal, Abbas (2004). "Quantitative study of high-dynamic-range image sensor architectures" (PDF). In Blouke, Morley M; Sampat, Nitin; Motta, Ricardo J (eds.). Sensors and Camera Systems for Scientific, Industrial, and Digital Photography Applications V. Vol. 5301. pp. 264–275. Bibcode:2004SPIE.5301..264K. doi:10.1117/12.544517. S2CID 14550103. Retrieved 17 December 2011.
- ^ Osuna, Rubén; García, Efraín. "Do Sensors "Outresolve" Lenses?". The Luminous Landscape. Archived from the original on 2 January 2010. Retrieved 21 December 2011.
- ^ Boreman, Glenn D. (2001). Modulation Transfer Function in Optical and Electro-Optical Systems. SPIE Press. p. 120. ISBN 978-0-8194-4143-0.
- ^ Ozaktas, Haldun M; Urey, Hakan; Lohmann, Adolf W. (1994). "Scaling of diffractive and refractive lenses for optical computing and interconnections". Applied Optics. 33 (17): 3782–3789. Bibcode:1994ApOpt..33.3782O. doi:10.1364/AO.33.003782. hdl:11693/13640. PMID 20885771. S2CID 1384331.
- ^ Goodman, Joseph W (2005). Introduction to Fourier optics, 3rd edition. Greenwood Village, Colorado: Roberts and Company. p. 26. ISBN 978-0-9747077-2-3.
- ^ Nasse, H. H. "From the Series of Articles on Lens Names: Tessar" (PDF). Carl Zeiss AG. Archived from the original (PDF) on 13 May 2012. Retrieved 19 December 2011.
- ^ Simon Crisp (21 March 2013). "Camera sensor size: Why does it matter and exactly how big are they?". Retrieved January 29, 2014.
- ^ Stanislav Utochkin. "Specifying active area size of the image sensor". Retrieved May 21, 2015.
- ^ Catrysse, Peter B.; Wandell, Brian A. (2005). "Roadmap for CMOS image sensors: Moore meets Planck and Sommerfeld" (PDF). In Sampat, Nitin; Dicarlo, Jeffrey M.; Motta, Ricardo J. (eds.). Digital Photography. Vol. 5678. p. 1. Bibcode:2005SPIE.5678....1C. CiteSeerX 10.1.1.80.1320. doi:10.1117/12.592483. S2CID 7068027. Archived from the original (PDF) on 13 January 2015. Retrieved 29 January 2012.
- ^ DxOmark. "F-stop blues". DxOMark Insights. Archived from the original on 25 January 2012. Retrieved 29 January 2012.
- ^ Aptina Imaging Corporation. "An Objective Look at FSI and BSI" (PDF). Aptina Technology White Paper. Retrieved 29 January 2012.
- ^ "Nikon unveils J1 small sensor mirrorless camera as part of Nikon 1 system", Digital Photography Review.
- ^ "Canon's Full Frame CMOS Sensors" (PDF) (Press release). 2006. Archived from the original (PDF) on 2012-10-28. Retrieved 2013-05-02.
- ^ https://www.gsmarena.com/apple_iphone_13-11103.php
- ^ http://europe.nokia.com/PRODUCT_METADATA_0/Products/Phones/8000-series/808/Nokia808PureView_Whitepaper.pdf Nokia PureView imaging technology whitepaper
- ^ "The Phase One P+ Product Range". PHASE ONE. Archived from the original on 2010-08-12. Retrieved 2010-06-07.
- ^ "Leica S2 with 56% larger sensor than full frame" (Press release). Leica. 2008-09-23. Retrieved 2010-06-07.
- ^ "Pentax unveils 40MP 645D medium format DSLR" (Press release). Pentax. 2010-03-10. Retrieved 2010-12-21.
- ^ Johnson, Allison (2016-06-22). "Medium-format mirrorless: Hasselblad unveils X1D". Digital Photography Review. Retrieved 2016-06-26.
- ^ "Fujifilm announces development of new medium format "GFX" mirroless camera system" (Press release). Fujifilm. 2016-09-19.[permanent dead link]
- ^ "Fujifilm's Medium Format GFX 50S to Ship in February for $6,500". 2017-01-19.
- ^ Staff (7 October 2002). "Making (some) sense out of sensor sizes". Digital Photography Review. Retrieved 29 June 2012.
- ^ Staff. "Image Sensor Format". Imaging Glossary Terms and Definitions. SPOT IMAGING SOLUTIONS. Archived from the original on 26 March 2015. Retrieved 3 June 2015.
- ^ Pogue, David (2010-12-22). "Small Cameras With Big Sensors, and How to Compare Them". The New York Times.
- ^ a b Bockaert, Vincent. "Sensor Sizes: Camera System: Glossary: Learn". Digital Photography Review. Archived from the original on 2013-01-25. Retrieved 2012-04-09.
- ^ "Making (Some) sense out of sensor sizes".
- ^ Camera Sensor Ratings Archived 2012-03-21 at the Wayback Machine DxOMark
- ^ Imaging-resource: Sample images Comparometer Imaging-resource
- ^ "Unravelling Sensor Sizes – Photo Review". www.photoreview.com.au. Retrieved 2016-09-22.
- ^ Nokia Lumia 720 – Full phone specifications, GSMArena.com, February 25, 2013, retrieved 2013-09-21
- ^ Camera sensor size: Why does it matter and exactly how big are they?, Gizmag, March 21, 2013, retrieved 2013-06-19
- ^ "Diagonal 5.822 mm (Type 1/3.09) 16Mega-Pixel CMOS Image Sensor with Square Pixel for Color Cameras" (PDF). Sony. Archived from the original (PDF) on 16 October 2019. Retrieved 16 October 2019.
- ^ Comparison of iPhone Specs, PhoneArena
- ^ "Diagonal 6.23 mm (Type 1/2.9) CMOS Image Sensor with Square Pixel for Color Cameras" (PDF). Sony. 2015. Retrieved 3 April 2019.
- ^ "iPhone XS Max teardown reveals new sensor with more focus pixels". Digital Photography Review. 27 September 2018. Retrieved 1 March 2019.
- ^ "Phantom 3 Professional - Let your creativity fly with a 4K camera in the sky. - DJI". DJI Official. Retrieved 2019-12-01.
- ^ "DJI - The World Leader in Camera Drones/Quadcopters for Aerial Photography". DJI Official. Retrieved 2019-12-01.
- ^ "Diagonal 7.87mm (Type 1/2.3) 20.7M Pixel CMOS Image Sensor with Square Pixel for Color Cameras" (PDF). Sony. September 2014. Archived from the original (PDF) on 3 April 2019. Retrieved 3 April 2019.
- ^ "Fujifilm FinePix F200EXR Sensor Info & Specs". www.digicamdb.com. Retrieved 2025-08-03.
- ^ "Samsung officially unveils 108MP ISOCELL Bright HMX mobile camera sensor". Digital Photography Review. Aug 12, 2019. Retrieved 16 Feb 2021.
- ^ "Diagonal 17.6 mm (Type 1.1) Approx. 12.37M-Effective Pixel Monochrome and Color CMOS Image Sensor" (PDF). Sony. March 2016. Archived from the original (PDF) on 15 December 2017. Retrieved 3 April 2019.
- ^ "Hasselblad X1D-II 50c Datasheet" (PDF). Hasselblad. 2019-06-01. Retrieved 2022-04-09.
- ^ "GFX 50s Specifications". Fujifilm. January 17, 2019. Retrieved 2022-04-09.
- ^ KODAK KAF-39000 IMAGE SENSOR, DEVICE PERFORMANCE SPECIFICATION (PDF), KODAK, April 30, 2010, retrieved 2014-02-09
- ^ Hasselblad H5D-60 medium-format DSLR camera, B&H PHOTO VIDEO, retrieved 2013-06-19
External links
[edit]- Eric Fossum: Photons to Bits and Beyond: The Science & Technology of Digital, Oct. 13, 2011 (YouTube Video of lecture)
- Joseph James: Equivalence at Joseph James Photography
- Simon Tindemans: Alternative photographic parameters: a format-independent approach at 21stcenturyshoebox
- Compact Camera High ISO modes: Separating the facts from the hype at dpreview.com, May 2007
- The best compromise for a compact camera is a sensor with 6 million pixels or better a sensor with a pixel size of >3μm at 6mpixel.org
- [1] at hasselblad.com
Image sensor format
View on GrokipediaFundamentals of Image Sensor Formats
Definition and Characteristics
An image sensor format refers to the physical dimensions, including width and height, and the aspect ratio of the photosensitive area within a digital image sensor, such as those employed in charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) technologies.[9] This format defines the overall shape and size of the sensor's active surface, which captures incoming light and converts it into electrical signals for image formation.[10] The dimensions are conventionally measured in millimeters, with the diagonal length serving as a standard metric for specifying the sensor's scale, often rooted in historical conventions where sizes are denoted as fractions of an inch—for instance, a "1-inch" format corresponds to a diagonal of approximately 16 mm.[2] Key characteristics of image sensor formats include their aspect ratios, which represent the proportional relationship between the sensor's width and height, influencing the shape of the captured image. Common aspect ratios encompass 3:2, prevalent in still photography for its compatibility with traditional film formats; 4:3, typical in compact and medium-format digital cameras; and 16:9, optimized for widescreen video applications.[11] Additionally, the format governs the potential pixel count, as the total resolution is determined by the physical area divided by the pixel pitch—the center-to-center distance between adjacent pixels, usually ranging from 2 to 30 micrometers.[10] Larger formats support either denser pixel arrays for higher resolution or wider pixel pitches for improved light-gathering efficiency, as a greater surface area collects more photons per exposure.[12] In photography and videography, the image sensor format fundamentally shapes system design by dictating lens compatibility, as the sensor must align with the lens's projected image circle to avoid vignetting, and by influencing the field of view for a fixed focal length lens.[13] This role extends to overall imaging architecture, where format selection balances portability, cost, and application-specific needs without directly addressing downstream performance metrics. The foundational sensor types—CCD and CMOS—underpin these formats: CCDs operate by sequentially transferring accumulated charge across the array to a single output amplifier, ensuring uniform response but requiring external processing; in contrast, CMOS sensors integrate amplification, noise reduction, and analog-to-digital conversion directly at each pixel, enabling lower power consumption and on-chip functionality.[14]Historical Development
The development of image sensor formats originated in the 1970s with pioneering charge-coupled device (CCD) prototypes. In 1975, Kodak engineer Steven Sasson assembled the first functional digital camera prototype, incorporating a Fairchild 100x100 pixel CCD sensor that yielded approximately 0.01 megapixels of resolution.[15] This innovation laid the groundwork for digital imaging, drawing inspiration from analog film standards, particularly the 35mm format's 36x24mm frame, which later shaped the full-frame digital sensor dimensions to ensure lens compatibility and optical familiarity. During the 1990s and 2000s, sensor formats advanced to support both professional and consumer digital single-lens reflex (DSLR) cameras. Nikon debuted the APS-C format in 1999 with the D1, employing a 23.7x15.6mm CCD sensor that cropped the 35mm field of view by a 1.5x factor, enabling affordable high-performance imaging.[16] Canon followed in 2002 by introducing full-frame sensors in the EOS-1Ds, featuring an 11.1-megapixel 35.8x23.8mm CMOS sensor that matched the 35mm film's imaging area for unaltered lens perspectives.[17] Concurrently, compact sensor formats proliferated in consumer point-and-shoot cameras, typically measuring around 1/2.3-inch (6.17x4.55mm), prioritizing portability over light-gathering capacity. The 2010s brought standardization and miniaturization, with the Micro Four Thirds format emerging in 2008 through a collaboration between Olympus and Panasonic, utilizing a 17.3x13mm sensor (2x crop factor) to foster compact mirrorless systems with interchangeable lenses.[18] Smartphone sensors, meanwhile, continued to shrink, reaching 1/2.5-inch sizes (approximately 5.76x4.29mm) and below by the mid-decade, accompanied by pixel pitches as small as 1μm to accommodate megapixel counts exceeding 12 in slim devices.[19] These developments balanced computational photography gains against reduced per-pixel light sensitivity. By the 2020s up to 2025, stacked CMOS architectures have facilitated high-resolution medium-format sensors, such as the 102-megapixel 44 mm × 33 mm back-illuminated stacked design in Fujifilm's GFX100 II, released in 2023, which enhances readout speeds for professional stills and video.[20] Global shutter implementations have also advanced for video-centric applications, notably Sony's full-frame stacked CMOS sensor in the 2023 Alpha 9 III, enabling distortion-free capture at up to 120 frames per second.[21] In the consumer smartphone sector, sensor sizes have grown during the 2020s, with flagship devices such as the Xiaomi 14 Ultra (2024) and Huawei Pura 80 Ultra (2025) featuring 1-inch sensors (diagonal ≈16 mm) to enhance low-light performance and image quality.[22][23]Physical Dimensions and Optical Interactions
Sensor Size and Aspect Ratios
Image sensor formats are typically described by their physical dimensions, including horizontal, vertical, and diagonal measurements, expressed either in millimeters for precision or in an archaic inch-based system derived from early video technology. The inch designations originated from vidicon tubes used in 1950s television cameras, where the nominal "inch" size referred to the outer tube diameter rather than the active imaging area; for instance, a "1-inch" vidicon had an effective picture area with a diagonal of approximately 16 mm.[24][25] In modern digital sensors, this convention persists, so a "1-inch" sensor measures 13.2 mm horizontally by 8.8 mm vertically, yielding a diagonal of about 15.9 mm, despite no actual dimension reaching 25.4 mm.[26][27] These measurements define the overall format, influencing the sensor's compatibility with lens image circles and the geometric projection of light onto the sensing surface.[28] Aspect ratios, expressed as the proportion of width to height, further shape the format's geometry and dictate how scenes are framed directly from the sensor without post-capture cropping. The 3:2 ratio, standard in digital single-lens reflex cameras, mirrors the dimensions of traditional 35 mm film and provides a balanced horizontal emphasis suitable for landscapes and portraits, capturing wider scenes relative to height.[29] In contrast, the 4:3 ratio, used in Four Thirds systems, offers a more square-like framing that preserves vertical detail for subjects like architecture or macro work, reducing the need to crop for square compositions. The 16:9 widescreen ratio, prevalent in video-oriented sensors, stretches horizontal coverage for cinematic or broadcast applications, enabling immersive wide-angle views but potentially compressing vertical elements in still imaging.[29] These ratios directly affect compositional framing by altering the field of view's proportions, allowing photographers to select formats that align with intended aspect without losing resolution to crops.[30] Sensors are classified by size based on diagonal dimensions, with full-frame formats measuring 36 mm × 24 mm, corresponding to a 43.3 mm diagonal that matches the exposure area of 35 mm film.[31] Medium format sensors exceed this scale, typically featuring diagonals greater than 43 mm—such as 48 mm × 36 mm with a 60 mm diagonal—to accommodate expansive imaging for professional applications requiring heightened detail.[32] Smaller formats, often under 20 mm diagonal, include compact types like the 1-inch sensor at 15.9 mm, which enable portable devices but constrain the angular coverage compared to larger counterparts.[26][2] Variations in format design include non-square pixels in certain video sensors, where individual pixels have unequal horizontal and vertical dimensions to match display standards like NTSC or PAL, optimizing data efficiency without altering the overall sensor shape.[33][34] Emerging experimental formats, such as curved sensors, deviate from flat planes to better mimic biological eyes and reduce optical aberrations; as of 2025, prototypes like NHK's 0.01 mm-thick bendable silicon sensors demonstrate viability for wide-field imaging but remain in research stages.[35][36]Active Sensing Area
The active sensing area of an image sensor refers to the central region composed of the photosite array, where individual pixels—each containing a photodetector such as a photodiode—capture incident light and convert it into electrical charge, excluding non-photosensitive elements like peripheral borders, interconnect wiring, and integrated amplifiers. This area is distinct from the overall sensor die, as the latter includes supporting circuitry that does not contribute to photon detection. The efficiency of light capture within each pixel is quantified by the fill factor, defined as the ratio of the light-sensitive surface area to the total pixel area, which typically ranges from 60% to 90% in modern CMOS sensors depending on pixel design and illumination architecture.[37] In sensor architecture, the active sensing area is primarily the pixel array, while peripheral circuitry—such as row and column decoders, analog-to-digital converters, and timing controllers—occupies the borders around it, potentially comprising 10-20% of the total die in compact designs. Back-illuminated sensors (BSI), introduced commercially by Sony in 2009 for consumer applications, relocate metal wiring and transistors to the front side while illuminating the photodiodes from the back, thereby increasing the effective active area efficiency and fill factor by reducing light obstruction and improving quantum efficiency to over 90% in some cases. This design shift, building on research from the early 2000s, minimizes shadowing from overlying structures and enhances light collection without altering the physical pixel layout.[38][39] Inactive borders in small-format sensors proportionally reduce the effective active sensing area relative to the quoted die dimensions, as circuitry overhead consumes a larger fraction of the limited space; for instance, a nominally "1-inch" sensor, derived from historical vidicon tube specifications, has an actual active diagonal of approximately 15.9 mm rather than a full 25.4 mm. This discrepancy arises because the designation refers to the outer tube diameter, not the light-capturing region, leading to a smaller usable area that impacts light-gathering capacity and format equivalence. Such borders can also introduce minor shading effects at the image periphery due to uneven light falloff near non-sensitive zones.[40][41] Recent advancements in organic image sensors and 3D-stacked CMOS designs have pushed active area utilization toward near-100% fill factors by decoupling photosensitive layers from underlying electronics. Organic photodiodes, overlaid directly on CMOS readout circuits, enable full-surface light detection without gaps for transistors, achieving up to 100% geometric fill factor as demonstrated in hybrid prototypes since the early 2020s. Similarly, post-2020 3D-stacked architectures vertically integrate logic and memory layers beneath the pixel array using through-silicon vias, freeing the top surface for maximum photodetector coverage and supporting higher-resolution formats with minimal efficiency loss.[42][43][44]Crop Factor and Equivalence
The crop factor, also known as the format factor or focal length multiplier, is defined as the ratio of the diagonal dimension of a full-frame (35 mm) sensor, approximately 43.3 mm, to the diagonal dimension of the sensor in question.[45][46] This ratio quantifies how a smaller sensor "crops" the image projected by a lens compared to the full-frame standard, effectively narrowing the field of view. The formula for calculating the crop factor is .[45][47] For example, an APS-C sensor with a diagonal of about 28.3 mm yields a crop factor of approximately 1.5×, while a Micro Four Thirds (MFT) sensor with a 21.6 mm diagonal results in a 2× crop factor.[48][49] Equivalence principles extend the crop factor to predict how images from different sensor formats can be made comparable in terms of angle of view, depth of field, and exposure. To achieve an equivalent angle of view, the focal length of a lens on a cropped sensor is multiplied by the crop factor; for instance, a 50 mm lens on an APS-C sensor produces a field of view similar to a 75 mm lens on full-frame.[50][46] For depth of field equivalence, the f-number must also be scaled by the crop factor, such that an f/2 aperture on an MFT sensor (2× crop) matches the depth of field of an f/4 aperture on full-frame.[51][52] These scalings derive from geometric optics and ensure that photographic parameters like focal length, f-number, and ISO are adjusted proportionally to the format diagonal for equivalent results across sensors.[52] In practical photography applications, the crop factor leads to a narrower field of view on smaller sensors, which can simulate longer focal lengths without physically longer lenses, beneficial for telephoto work but challenging for wide-angle shots.[50][46] Regarding exposure equivalence, larger sensors collect more total photons for the same scene luminance and exposure settings due to their greater area, improving signal-to-noise ratio even if per-unit-area light density remains constant.[51][49] Limitations of the crop factor concept arise when applied to sensors larger than full-frame, such as medium format, where the crop factor falls below 1× (e.g., 0.79× for a 44 × 33 mm sensor), inverting the equivalence and widening the field of view relative to full-frame.[46][53] Additionally, digital cropping within a sensor further increases the effective crop factor, but this does not alter the physical sensor's light-gathering capacity.[45][48]Impacts on Image Quality
Depth of Field Effects
Depth of field (DoF) refers to the range of distances within a scene that appear acceptably sharp in an image. Image sensor format plays a key role in determining DoF through its influence on the crop factor and the circle of confusion (CoC), which defines the maximum acceptable blur for perceived sharpness. Smaller sensor formats, with higher crop factors, yield deeper DoF for equivalent framing and aperture compared to larger formats like full-frame, as the relative CoC is larger on smaller sensors, extending the zone of sharpness. This scaling with crop factor means that achieving the same field of view on a smaller sensor requires a shorter focal length, which inherently deepens DoF at the same f-stop.[54] The hyperfocal distance , the closest focus distance at which DoF extends to infinity, illustrates this effect and is calculated as where is the focal length, is the f-number, and is the CoC diameter. For larger sensors, is larger (e.g., 0.03 mm vs. 0.02 mm for APS-C) to ensure equivalent sharpness when images are viewed at standard sizes, resulting in a shorter hyperfocal distance and thus shallower overall DoF.[55][56] A practical comparison highlights these differences: a 50 mm f/1.8 lens on a full-frame sensor produces a shallower DoF than the same lens on an APS-C sensor (1.5x crop factor) for the same subject distance, due to the narrower field of view on the smaller sensor, which provides a tighter framing equivalent to a longer focal length on full-frame. To match both the tighter framing and the shallower DoF of the full-frame 50mm f/1.8 on APS-C, the setup would need approximately a 50 mm f/1.2 lens, demonstrating how full-frame allows shallower DoF at equivalent f-numbers for the same wide-angle framing, but for equivalent framing, smaller sensors require wider apertures for similar background blur. This capability of full-frame sensors enables more pronounced and creamy bokeh effects, providing an advantage in genres requiring subject isolation.[57][58][59] In genres like portraiture and macro photography, the deeper DoF of smaller sensors limits bokeh and subject isolation, often requiring photographers to stop down less or use closer distances to approximate the shallow focus possible on larger formats.[60] In contrast, video production benefits from this trait in compact cameras, where deeper DoF maintains focus across moving subjects and backgrounds, reducing the need for continuous refocusing in dynamic scenes.[54] To counteract deeper DoF on smaller sensors, faster lenses with maximum apertures like f/1.2 or f/1.4 are employed to widen the aperture relative to equivalence, enabling shallower focus. As of 2025, AI-based post-processing mitigates this further by simulating defocus blur and bokeh from in-focus images through depth estimation and generative models.[61]Diffraction and Resolution Limits
Diffraction imposes a fundamental optical limit on the resolution achievable by image sensors, arising from the wave nature of light as it passes through the lens aperture. The smallest resolvable detail is determined by the Airy disk, the diffraction pattern produced by a point source of light, with its radius given approximately by , where is the wavelength of light (typically around 550 nm for visible light) and is the f-number of the lens.[62] The diffraction limit occurs when the Airy disk size becomes comparable to or larger than the pixel pitch, causing overlapping patterns that blur fine details across multiple pixels. In image sensors, smaller formats with higher pixel densities exacerbate this limit because they employ finer pixel pitches, leading to diffraction effects at wider apertures compared to larger sensors. For instance, compact sensors with 1 μm pixels encounter significant diffraction softening at f/2.8, where the Airy disk diameter spans multiple pixels and reduces effective resolution, whereas full-frame sensors with typical 5-6 μm pixels can maintain sharpness up to f/11 before similar impacts. Thus, full-frame sensors generally provide sharper details due to reduced diffraction limitations at common apertures compared to smaller sensors with higher pixel densities.[63][64] This interaction highlights how sensor size indirectly influences the usable aperture range: smaller sensors hit the diffraction barrier sooner when pursuing high resolution through dense pixel arrays.[65] Resolution metrics, such as modulation transfer function (MTF) curves, quantify this softening by illustrating how diffraction attenuates contrast at high spatial frequencies. Diffraction causes a characteristic roll-off in MTF beyond the cutoff frequency, approximately , blurring edges and fine textures in a manner independent of lens aberrations but directly tied to aperture and wavelength.[66] Practically, this sets pixel density limits; for example, 100 MP full-frame sensors (with ~3 μm pixels) remain viable for professional use at common apertures like f/5.6-f/8, preserving usable MTF above 50% at Nyquist frequencies, while 200 MP compact sensors on smartphone formats (~0.6 μm pixels) suffer pronounced softening even at f/1.8-f/2, limiting real-world detail extraction despite raw pixel counts.[67] Advancements in sensor design incorporate anti-aliasing filters to suppress aliasing artifacts in high-density arrays, allowing operation closer to the diffraction limit without excessive moiré, while post-processing software in tools like Canon Digital Photo Professional and DxO PhotoLab applies targeted sharpening algorithms to partially restore contrast lost to diffraction, extending the effective resolution range for small-format sensors.[68][69]Lens Image Circle Compatibility
The image circle of a lens is defined as the diameter of the illuminated circular area projected onto the focal plane, which must fully encompass the sensor's active area to ensure complete coverage without geometric truncation. For a full-frame sensor with dimensions of 36 mm × 24 mm, the required image circle diameter is approximately 43.3 mm, matching the sensor's diagonal measurement. In contrast, an APS-C sensor, typically sized around 23.5 mm × 15.6 mm, necessitates an image circle of about 28 mm to cover its diagonal. Sensor format significantly influences lens design trade-offs, as smaller formats like APS-C enable lenses with reduced image circle requirements, leading to more compact optics with fewer and smaller glass elements, thereby lowering manufacturing costs, weight, and overall size. Larger formats, such as full-frame or medium format, demand expansive image circles that necessitate bulkier, heavier lenses with additional corrective elements, escalating production expenses and physical demands on camera systems. Compatibility between lenses and sensors hinges on image circle size relative to format; full-frame lenses, with their broader coverage, seamlessly pair with smaller APS-C sensors without coverage shortfalls. However, APS-C lenses on full-frame bodies often result in incomplete sensor illumination, causing edge cutoff, which can be mitigated through in-camera crop modes that digitally restrict the active area to the lens's image circle diameter. As of 2025, lens design evolutions emphasize modularity for hybrid sensor formats, with interchangeable optical modules enabling adjustable image circles to accommodate varying sensor sizes in compact devices like smartphones.[70] Additionally, telecentric lens architectures are gaining prominence in machine vision, providing parallel chief rays for uniform sensor coverage across formats, minimizing perspective distortion in precision applications.Noise and Performance Metrics
Exposure and Photon Collection
The total number of photons collected by an image sensor depends on the sensor's active area, the illuminance at the image plane (determined by scene luminance and lens f-number), the exposure time, and the sensor's quantum efficiency, which represents the fraction of incident photons converted to photoelectrons. For silicon-based sensors common in digital imaging, quantum efficiency typically ranges from 50% to 90% across the visible spectrum, with higher values achievable in back-illuminated designs.[10][71] The relationship can be expressed as: where is the number of photoelectrons, is the quantum efficiency, is the sensor area, is the illuminance, is the exposure time, and is the photon energy. This equation highlights that, for a fixed illuminance and exposure duration, photon collection scales directly with sensor area.[72] Larger sensor formats collect more total light under identical f-stop and scene conditions because the f-number governs illuminance uniformly across the focal plane, while the increased area captures a greater aggregate photon flux. This advantage enables larger sensors to achieve equivalent signal strength at lower ISO sensitivities, reducing the need for amplification and thereby preserving exposure latitude before noise becomes prominent. For instance, a full-frame sensor (approximately 864 mm²) gathers roughly four times the light of a Micro Four Thirds sensor (approximately 225 mm²) for the same settings, equivalent to a 2-stop advantage in light collection. This greater photon collection contributes to cleaner low-light performance in full-frame sensors compared to smaller formats.[73][74][75] Within the exposure triangle—comprising aperture, shutter speed, and ISO—sensor size indirectly influences effective photon capture by altering total light gathered without changing per-unit-area exposure. With identical shutter speed and ISO settings, a larger sensor yields a higher total signal from the same illuminance, effectively providing greater headroom for post-processing while maintaining consistent image brightness after amplification. This distinction underscores how sensor format adapts the triangle's outcomes, prioritizing total photon volume over localized intensity.[76]Noise Sources and Mitigation
Image sensors are susceptible to several primary noise sources that degrade signal quality, with their prominence influenced by sensor format size. Shot noise, arising from the random arrival of photons, follows Poisson statistics where the noise standard deviation is , with representing the number of photons collected per pixel.[77] In smaller format sensors, pixels are typically smaller to maintain resolution, resulting in fewer photons per pixel and thus a higher relative shot noise level compared to larger formats with bigger pixels that collect more photons.[78][79] Read noise originates from electronic contributions in the amplifier and analog-to-digital converter (ADC), typically ranging from 2-5 electrons RMS in modern CMOS sensors. This signal-independent noise becomes less dominant in larger pixels found in bigger sensor formats, as the increased photon signal amplifies the signal-to-noise ratio, overshadowing the fixed read noise floor.[80][78] Dark noise stems from thermal generation of electrons in the absence of light, producing a dark current of typically 0.01-1 electrons per second per pixel at room temperature for modern CMOS sensors.[81] In large-format scientific sensors, this noise is mitigated through cooling techniques, such as thermoelectric systems, which reduce thermal electron generation rates exponentially with temperature decrease.[82] Several strategies address these noise sources, often enhanced by larger sensor formats. Back-side illuminated (BSI) architectures relocate wiring to the backside of the sensor, improving quantum efficiency and reducing shot and read noise by allowing more photons to reach the photodiode. Dual-gain ISO mechanisms, introduced in 2020s CMOS designs, switch between high and low conversion gains to minimize read noise at higher sensitivities while preserving dynamic range.[83] Pixel binning combines adjacent pixels to form larger effective pixels, averaging out read and shot noise for improved signal-to-noise ratio in low-light conditions.[84] Overall, larger sensor formats inherently lower noise through bigger pixels—for instance, 4 μm pixels versus 1 μm—by collecting more photons and diluting electronic noise contributions.[78][85]Dynamic Range Considerations
Dynamic range (DR) in image sensors quantifies the ability to capture a wide range of light intensities, from the darkest shadows to the brightest highlights, without loss of detail due to clipping or excessive noise. It is mathematically defined as DR = 20 \log_{10} \left( \frac{\text{full well capacity}}{\text{[noise floor](/page/Noise_floor)}} \right) in decibels, where full well capacity represents the maximum number of electrons a pixel can store before saturation, and the noise floor is the minimum detectable signal limited primarily by sensor noise sources.[86][87] Consumer-grade sensors typically achieve 12-15 stops of dynamic range, equivalent to roughly 72-90 dB, enabling faithful reproduction of scenes with moderate contrast.[88][89] Sensor format size directly influences dynamic range by allowing larger pixels that increase full well capacity, thereby improving the signal-to-noise ratio. For instance, full-frame sensors often feature pixels with full well capacities around 50 ke⁻, compared to approximately 10 ke⁻ in smaller smartphone sensors, due to the greater physical area available for charge storage. Consequently, full-frame sensors offer superior dynamic range over smaller sensors.[90][91][92] This scaling typically extends dynamic range by 1-2 stops for each doubling of sensor area, as larger formats collect more photons per pixel, reducing the relative impact of noise on the overall signal.[93] Noise sources, such as read noise and shot noise, primarily determine the noise floor and thus cap the achievable dynamic range across all formats.[94] Key factors in dynamic range performance include the recoverability of details in shadows and highlights during post-processing, as well as the avoidance of clipping where bright areas wash out or dark regions become featureless black. Larger formats excel here by providing headroom for non-destructive adjustments, preserving tonal gradations that smaller sensors might lose. To compensate, compact sensors in smartphones and similar devices employ high dynamic range (HDR) modes, which computationally stack multiple exposures at varying intensities to synthesize an extended range, effectively mitigating clipping in high-contrast scenes.[95][96] As of 2025, medium-format sensors routinely exceed 14 stops of dynamic range, benefiting from their expansive area and advanced architectures for professional applications requiring maximal tonal fidelity. In contrast, smartphone sensors achieve around 12 stops natively but leverage computational stacking to approach or match this in practical use, demonstrating how format size interacts with processing to balance performance.[97][98]Optical Aberrations and Artifacts
Vignetting and Shading Causes
Optical vignetting arises from the geometry of the lens system, leading to a reduction in illumination toward the image periphery. This falloff follows the cos⁴θ law, where θ represents the angle from the optical axis, primarily due to the combined effects of cosine variations in projected area, distance, and obliquity of rays passing through lens elements and stops.[99] Natural vignetting, inherent to lens design, stems from the natural cosine-fourth illumination falloff as off-axis light rays traverse the lens at oblique angles, reducing the effective aperture size for peripheral image points.[100] In contrast, mechanical vignetting occurs when physical obstructions, such as lens hoods, filter holders, or mounts, block portions of the light beam for off-axis rays, causing abrupt darkening at the edges.[100] Sensor shading, distinct from optical vignetting, originates within the image sensor itself and manifests as non-uniform pixel sensitivity across the array. This variation is exacerbated by the angled incidence of off-axis rays, particularly in non-telecentric lens designs where chief ray angles deviate significantly from normal, leading to incomplete illumination of photodiodes.[101] Microlenses, intended to focus light onto photodiodes, contribute to shading when off-axis rays strike at steep angles, reducing quantum efficiency (QE) at peripheral pixels by up to 20-30% in CMOS sensors without optimized microlens tilt.[102] Additionally, the color filter array (CFA) introduces color-dependent shading, as off-angle light causes crosstalk and wavelength-specific sensitivity drops, with blue channels often most affected due to their narrower spectral response.[102] Vignetting and shading are quantified by measuring the percentage drop in illumination or gray level from the image center to the corners, typically under uniform illumination, where a 20-50% reduction indicates moderate effects depending on the lens-sensor combination.[103] In practice, this is assessed using flat-field images, revealing radial falloff profiles that combine optical and sensor contributions.[104] During RAW image processing, shading calibration applies per-pixel gain corrections derived from factory or in-field flat-field captures to compensate for these non-uniformities, ensuring even tonal response across the sensor. This step, often performed early in the pipeline, normalizes pixel responses before demosaicing and tone mapping. Image sensor format influences these artifacts distinctly: smaller formats exhibit reduced optical vignetting when paired with appropriately scaled lenses that maintain a matching image circle, and generally experience less pronounced sensor shading due to shallower chief ray angles relative to the sensor plane for equivalent fields of view.[101] Larger formats, conversely, capture more oblique rays across their extent, amplifying both effects unless telecentric optics are employed.[100]Sensor Size Influence on Artifacts
The size of an image sensor significantly modulates the visibility of optical artifacts such as vignetting and shading, primarily through its interaction with the lens's illumination profile and the sensor's architectural features. Larger format sensors, such as full-frame, capture a broader field of view for a given focal length, thereby exposing more of the lens's inherent peripheral light falloff and making vignetting more apparent across the image frame.[105][101] In contrast, smaller sensors crop into the central portion of the lens's image circle, potentially mitigating some wide-angle vignetting but introducing other challenges related to off-axis light incidence. The active area of the sensor, which defines the effective photon-collecting region, further influences shading non-uniformity in peripheral zones.[106] Artifact severity varies notably between formats, with compact sensors smaller than 1/2 inch often exhibiting amplified corner shading due to heightened pixel crosstalk and color non-uniformity under oblique illumination angles.[106] These effects stem from the tighter packing of photosites, which exacerbates sensitivity to chief ray angle mismatches and leads to substantial luminance drops at the edges. Full-frame sensors, benefiting from larger individual pixels, tend to average out minor illumination inconsistencies more effectively, resulting in less pronounced per-area shading despite the overall wider exposure to falloff.[107][108] Corrections for sensor size-induced artifacts typically involve a combination of hardware and software approaches tailored to the format. In-camera profiles apply pre-calibrated adjustments to compensate for known shading patterns, while tools like Adobe Lens Correction use lens-specific data to mitigate vignetting through parametric curve fitting.[109] Flat-fielding techniques, which involve capturing a uniform reference image and dividing the raw data by it, provide a robust method for normalizing illumination variations across the sensor.[110] Beyond vignetting and shading, sensor size influences other distortions, including field curvature and purple fringing. Large format sensors amplify field curvature challenges, as maintaining a flat focal plane across an extended image circle demands more precise lens-sensor alignment.[111] Conversely, small high-density sensors are more susceptible to purple fringing, a blooming artifact arising from charge overflow in saturated edge pixels under intense light.[112]Standard and Emerging Formats
Consumer and Professional Formats
The full-frame sensor format, measuring 36 × 24 mm with a 3:2 aspect ratio, serves as the standard for professional interchangeable-lens cameras, including DSLRs and mirrorless models.[75] This size matches the dimensions of traditional 35 mm film, enabling compatibility with a wide range of legacy and modern lenses designed for optimal performance across the entire image circle.[75] Prominent examples include the Canon EOS R5, which features a 45-megapixel full-frame CMOS sensor, and the Sony α1, equipped with a 50.1-megapixel stacked Exmor RS CMOS sensor, both prioritizing high-resolution stills and 8K video in professional workflows.[113][114] APS-C sensors, typically sized at approximately 23.5 × 15.6 mm for Nikon and Sony implementations (with Canon's variant at 22.3 × 14.9 mm), offer a crop factor of about 1.5× (or 1.6× for Canon), effectively extending the focal length of lenses for a narrower field of view.[115][116] These formats are prevalent in hybrid cameras that balance photography and videography, such as the Sony α6700 and Canon EOS R7, which support 4K video recording alongside burst shooting rates suitable for action and events.[117][118] The APS-H format, measuring 28.7 × 19 mm with a 1.3× crop factor, was historically employed by Canon in professional sports and wildlife cameras like the EOS-1D series, providing a compromise between full-frame image quality and the extended reach of cropped sensors for telephoto applications.[119][120] By 2025, APS-H has become rare, with no major manufacturers producing new models in this size, as full-frame and APS-C options have dominated due to advancements in sensor technology and lens ecosystems.[121] Full-frame sensors excel in low-light and studio environments, where their larger pixel areas—typically 24 to 60 megapixels—gather more photons per site for reduced noise and wider dynamic range at high ISOs.[75][122] In contrast, APS-C sensors, often ranging from 20 to 40 megapixels, prioritize portability, enabling lighter camera bodies and more compact lens designs ideal for travel, street, and hybrid shooting scenarios.[123] The crop factor in these formats briefly enhances effective reach for telephoto work without additional magnification tools.[116]Compact and Specialized Sensors
Compact and specialized image sensors cater to applications requiring portability, specific form factors, or unique imaging needs beyond standard consumer formats. These sensors are typically smaller than full-frame or APS-C equivalents, enabling integration into devices like point-and-shoot cameras, smartphones, and industrial equipment, though they often contend with challenges such as increased noise from smaller pixel sizes.[124][125] Among small formats, the 1/2.3-inch sensor, measuring approximately 6.17 mm × 4.55 mm, has been widely used in point-and-shoot compact cameras for its balance of size and resolution, allowing for slim designs in models like those from Canon and Nikon.[124][125] Larger small formats, such as the 1/1.7-inch sensor with an area of about 43 mm², appeared in premium compact cameras from brands like Panasonic and Casio, offering improved low-light performance over smaller siblings due to greater light-gathering capacity.[126][127] In smartphones, sensor sizes have trended upward in 2025 flagships, with 1/1.3-inch formats becoming common for main cameras, as seen in devices like the Samsung Galaxy S25 Ultra and various models using OmniVision's OV48C or OV50K40 sensors, which support high-resolution imaging up to 50 MP or 200 MP while fitting slim chassis. Stacked CMOS sensors in these devices enable faster readout speeds and reduced rolling shutter distortion.[128][129][130] The Micro Four Thirds format, standardized at 17.3 mm × 13 mm with a 2× crop factor relative to full-frame, powers interchangeable-lens systems from Olympus and Panasonic, excelling in hybrid video and still photography applications due to its compact lenses and robust stabilization features.[131][132] Specialized sensors include line-scan types, which feature a single line of pixels with variable widths (often thousands of pixels long but narrow in height) for industrial applications like inspecting continuous materials in manufacturing, such as textiles or printed circuits, where they enable high-speed, seamless imaging of moving surfaces.[133][134] Global shutter formats, avoiding rolling shutter distortions, are available in 1-inch sizes for dynamic scenarios, including cinema drones equipped with sensors like onsemi's XGS8000 (1/1.1-inch, 8.8 MP), which capture blur-free 4K footage at up to 120 fps during aerial motion.[135][136] Emerging trends in 2025 include quad-Bayer pixel arrangements in mobile sensors, where four pixels share a color filter to enhance low-light sensitivity by binning signals for effective larger pixel performance, as implemented in flagship phones for noise reduction in dim conditions.[137][138] Flexible image sensors, often around 5 mm × 5 mm or smaller, are advancing for wearables, with conformable thin designs from Japan Display Incorporated enabling bendable integration into smart textiles for health monitoring or augmented reality overlays.[139]Format Comparison Table
The following table provides a comparative overview of major image sensor formats, including dimensions, key metrics, and applications. Data on sizes, diagonals, crop factors, and aspect ratios are standardized based on common industry specifications, with variations noted where applicable (e.g., manufacturer-specific APS-C implementations). Crop factor is calculated relative to full-frame (35mm equivalent diagonal of 43.3 mm). Relative light collection is expressed as the approximate sensor area percentage compared to full-frame (864 mm² area), indicating photon-gathering potential. Pixel density ranges reflect typical resolutions in recent models (up to 2025), varying by pixel count but influencing noise and detail. Emerging formats, such as those optimized for 8K video, often favor larger sensors like medium format to maintain low pixel density while supporting high resolutions.| Format Name | Dimensions (mm, width × height) | Diagonal (mm) | Crop Factor | Aspect Ratio | Typical Use | Example Cameras (up to 2025 models) | Relative Light Collection (%) | Typical Pixel Density Range (MP/cm²) |
|---|---|---|---|---|---|---|---|---|
| Full-frame | 36 × 24 | 43.3 | 1 | 3:2 | Professional stills, video production, low-light photography | Sony α7 IV (2021), Canon EOS R5 Mark II (2024), Nikon Z8 (2023) | 100 | 2–7 |
| APS-C (Nikon/Sony/Fujifilm) | 23.5 × 15.6 | 28.2 | 1.5 | 3:2 | Enthusiast mirrorless/DSLR, sports/wildlife with reach advantage | Sony α6700 (2023), Fujifilm X-T5 (2022), Nikon Z50 II (2024) | 42 | 3–10 |
| APS-C (Canon) | 22.3 × 14.9 | 26.8 | 1.6 | 3:2 | Hybrid photo/video, compact professional setups | Canon EOS R7 (2022), Canon EOS R10 (2022) | 39 | 4–11 |
| Micro Four Thirds (MFT) | 17.3 × 13 | 21.6 | 2 | 4:3 | Compact mirrorless systems, video, travel photography | OM System OM-1 Mark II (2024), Panasonic Lumix GH6 (2022) | 26 | 5–12 |
| 1-inch Type | 13.2 × 8.8 (3:2) or 12.8 × 9.6 (4:3) | 16 | 2.7 | 3:2 or 4:3 | Premium compact cameras, drones, action video | Sony ZV-1 II (2023), Canon PowerShot G5 X Mark II (2019) | 13 | 8–15 |
| 1/2.3-inch | 6.17 × 4.55 | 7.7 | 5.6 | 4:3 | Point-and-shoot compacts, smartphones, entry-level superzooms | Canon PowerShot SX740 HS (2018), Sony Cyber-shot DSC-HX99 (2018) | 3.2 | 15–25 |
| Medium Format (44 × 33 mm) | 44 × 33 | 55 | 0.79 | 4:3 or 3:2 | Studio portraiture, landscapes, high-resolution commercial | Fujifilm GFX 100 II (2023), Hasselblad X2D 100C (2022) | 168 | 1–3 |
| Large Format (53.4 × 40 mm) | 53.4 × 40 | 66.6 | 0.65 | 4:3 | Technical/architectural photography, cinema (e.g., 8K standards) | Phase One XC (2023), Hasselblad H6D-400c MS (2018) | 247 | 0.5–2 |