Digital cameras use a sensor that captures light to take a picture. The size of the sensor affects how your images look, so you̵
Full frame versus crop sensor
Before digital cameras entered the market, the most popular film for photography was the 35mm format. It is 36mm x 24mm (1.4 “x 0.94”) in size.
Full-frame cameras use a digital sensor that is about the same size as 35mm film. This was useful for the transition between film and digital as it made things look alike as much as possible. Photographers could use the same lenses, and if they used the same settings, the images would look similar.
Full-frame sensors, however, are quite large and expensive. They are much larger than it takes to take good digital photos, so most consumer cameras use a smaller, cheaper, “cropped” sensor. (For comparison, a full-frame sensor is about 30 times the size of the 1 / 2.55 ″ sensor in the iPhone 12.)
For DSLRs and mirrorless cameras, the most common crop sensor size is APS-C, which is approximately 24mm x 16mm. The next size smaller, used in some mirrorless and compact cameras, is Micro 4/3, which is 17mm x 13mm.
You probably have a crop sensor camera
If you have a consumer DSLR like a Canon Rebel T8i, Nikon D3500 or one of their predecessors, you have a crop sensor camera. There simply aren’t any entry-level full-frame cameras.
If you’ve purchased an older, pre-owned DSLR, especially if it looks like a professional camera, it could be full-frame. Some of the most popular models of the past decade are:
- Canon 5D, 5D Mk II, 5D Mk III, 5D Mk IV, 6D and 6D Mk II.
- Nikon D600, D610, D700, D750, D780, D800, D810 and D850.
If your camera isn’t on the list, the easiest way to double check it is to google the make and model number. Unless it is explicitly stated to be full-frame, it will almost certainly use a smaller sensor.
Note: There is a small chance that the sensor is a medium or large size, both of which are larger than 35mm. If so, you’ve got your hands on a very expensive and sought-after package!
What does it really matter?
Full frame and crop sensor cameras are a bit of a throwback. Sensor technology has come so far with smartphones that the size of the sensor has never been more important to the quality of the photos you can take. However, that’s not to say that sensor size doesn’t affect things.
The most relevant, especially when reading photography tutorials, is the crop factor. Due to the way lenses work, a small sensor gets more magnification from the same lens focal length. If you put a 50mm lens on both a full frame and a crop sensor camera, you get a different field of view.
This is the full frame:
This (seemingly zoomed) image is from the crop sensor:
The relationship between the lens focal length and the apparent, or full-frame equivalent focal length, is the crop factor. It is normally between 1.5 and 1.6, so the 50mm lens on the crop camera is equivalent to an 80mm lens on a full-frame camera.
Here’s a comparison with an 85mm lens on a full-frame camera:
Read our full crop factor walkthrough for more information.
Larger sensors also perform better in low light, although this is unlikely in most cases. The real benefits of full-frame cameras are often that they are built like tanks for professionals and have more manual controls and options.
RELATED: What Is DSLR Crop Factor (And Why Should I Worry)
Do I need a full-frame camera?
Most people don’t really need a full-frame camera. If you are just starting out in photography, you don’t need to upgrade. Whatever you have lying around, or even your smartphone, it’s perfect for learning.
However, if you’re in the market for a camera and budget isn’t an issue, you probably want a full-frame mirrorless camera. For more on this, check out my camera buying advice on our sister site ReviewGeek.
RELATED: Is it worth buying a mirrorless camera yet?