Short Description

Image Sensor
Canon CMOS sensorPhoto of a Canon CMOS sensor

The sensor size is the physical dimensions of the cameras image sensor. This is the heart of the digital camera, this is essentially your "film". Typically the larger the sensor the better. Larger sensors permit more light per pixel permitting lower noise and higher quality conversion of light to a RGB value that is most accurate and contains the highest range of contrast and color depth. There are 7 main sensor sizes but you can primarily group all the sensors into two groups: small and large.

Small Digital Camera Sensors

Great 1/1.7" Digital Camera
Placeholder The Panasonic Lumix DC-FZ1000 II is one of the best 1/1.7" digicams.

Small sensors range between 1/3.6" (4x3mm) and 1/1.7" (7x5mm). Although the differences seem small 1/1.7" sensors offer 35mm² of sensor area while 1/3.6" only offer 12mm². 1/1.7" sensors are typically used in high end digicams that tend to produce better quality photos, largely because their sensors large (3X larger than 1/3.6") permitting cleaner pixels and lower noise at higher ISOs. Small sensors are only used in digicams, no SLRs use them, they are simply too small of a sensor even at the top of the size range. The major advantage of a small sensor is it permits smaller lenses and camera bodies, stuffing a full frame sensor into a ultra compact with decent zoom just isn't going to happen. If you want small portable size and zoom lenses that can slide inside a tiny camera you trade off having a small sensor.

Large Digital Camera Sensors

Large sensors range between 18x14mm(Four Thirds) and 36x24mm(full frame). These sensors are typically reserved for SLRs but there is a demand by enthusiasts for large sensors in small packages and as such you can find these sensors in select few boutique digicams as well as most mirrorless interchangeable lens cameras. These sensors are much larger than the small sensor group, the smallest large sensor, Four Thirds @ 18x14mm is still 7X larger than the largest small sensor - 1/1.7" @ 7x5mm. Large sensors inherently provide better cleaner images, they offer higher true resolution, larger pixels, better color depth and great dynamic range. For these reasons they are favored in SLRs which place a focus on quality over convenience.

Crop Factor on Large Sensors

When using interchangeable lenses the crop factor is important, because most large sensor cameras have interchangeable lenses the crop factor should be considered. The crop factor section provides a good overview.

Top Small Sensor Cameras

The following are the top small sensor cameras, providing a strong mix of size, feature, convenience and quality.

Green arrow See more of the top compact cameras with large sensors

Compact Large Sensor Cameras that Shoot Video

The following are the top large sensor cameras that are mid size or smaller and also shoot video. These represent high quality portable digital cameras that are a strong middle ground between large SLRs and compact digicams.

Green arrow See more of the top mid-size cameras with large sensors that shoot HD video


Showing 13 comments

Avatar for KennyBoy019 KennyBoy019 (7:17 PM, October 13, 2014)
Yes, but that's a digital MEDIUM FORMAT camera. Apples to oranges, if you will. Not really comparable.
Simeon (10:28 PM, October 25, 2012)
In terms of megapixels, a larger sensor is undoubtedly better, as more pixel can be taken per picture. In terms of light sensitivity, a larger sensor means squat if the pixel size is the same or shrinks. If the sensor size increases, and the megapixels are not proportionally increased, then light sensitivity will increase by virtue of a larger pixel size. You can always adjust the amount of light coming into the sensor via shutter speed and aperture, so saturating pixels (ie. "clipping") is not an issue. The real issue is an individual pixel's light sensitivity.
Avatar for Joe93444 Joe93444 (2:51 AM, June 22, 2012)
I would guess this is a dead thread...but this page shows the Sony RX100 has a 1/1.7" sensor in a boxed frame top right under the Canon CMOS boxed frame immediately above.  The description of the same  RX100 under "Top Small Sensor Cameras" indicates (correctly) that the RX100 has a 1" sensor...a lot bigger than 1/1.7".  It seems likely that if a Canon S95 makes the Top list...its replacement, the S100,  might also be on the list.  Just a thought.
Avatar for Mike Svitek Mike Svitek (4:08 AM, April 22, 2012)
errrr... isn't the D700 cheaper than the D800?!
Its still a full-frame camera
Avatar for Mike Svitek Mike Svitek (4:06 AM, April 22, 2012)
Larger sensor = Larger photosites on pixels = More light per pixel = Less noise = Better shot
Avatar for Mike Svitek Mike Svitek (4:05 AM, April 22, 2012)
I just realized that the Leica M9 is not even mentioned on this page! :(
Its the only mirrorless with a FULL-FRME SENSOR... it deserves a spot in this article!
Yohanes Martino (11:14 AM, March 24, 2012)
Why Snapsort said that Four Thirds sensor with size of 17.3mm X 13mm is smaller than average? But the Four Thirds Sensor size from the Four Thirds standard is 17.3mm X 13mm.
Avatar for Mike Svitek Mike Svitek (9:26 PM, January 18, 2012)
Technically, there are sensors much larger than Full Frame. The Pentax 645D, for example, uses a HUGE 44x33mm sensor, which is far larger than any full frame sensor. 
Bob (4:07 AM, December 22, 2011)
A larger sensor can accumulate more light, giving better low light performance. I have yet to see a review of cameras that includes photos from various size sensors that doesn't show a huge improvement in color and contrast as sensor size increases.
Avatar for Tyler 1 Tyler 1 (8:15 AM, October 04, 2011)
The crop factor info on this page is misleading, and just confuses people. It's not important when using the correct lenses for your camera.  
It's only relevant if you're using lenses designed for a different camera.

Actually, this whole page is confusing. It says "Larger sensors permit more light per pixel", which is wrong. It actually permits LESS light per pixel, which allows the pixel to function without being overloaded ("clipping").

The only relationship I can find between sensor size and image quality is that a larger sensor allows larger pixels, and larger pixels are less sensitive to the blur caused by overlapping light waves. The light waves are spread out more so they don't interfere with each other. I can't think of any other reason why a larger sensor would be better than a small one.

Small sensors are better, if all other things are equal, because they make it possible for the camera to have much more capability in a smaller size (depth of field, zoom, etc). If the sensor is big, but doesn't have large pixels, then I don't think there's any advantage, but it will have many disadvantages.
Avatar for Snapsort Snapsort (6:33 PM, February 08, 2011)
Thanks again, we've fixed that up.
Avatar for Snapsort Snapsort (2:28 AM, February 05, 2011)
Thanks for pointing that out, we'll fix that up!
Foo (2:04 AM, February 05, 2011)
The "Cheapest Full Frame DSLR" is proclaiming D3S as such, despite D700 being half the price. Fix it to select the camera from the database properly?