If you’re shopping for a DSLR or mirror less camera this season, you may hear the terms cropped or full-frame sensor pop up. Essentially, these are describing the size of the sensor within the camera. Full frame sensors are generally only found on cameras considered for pros, while cropped sensors are most common and can appear throughout product lines.
Digital sensor sizes vary greatly between camera models and manufacturers. This is why the 35mm frame from a traditional film camera is used as a standard for comparison. This is often referred to as full frame size. Although a full-frame sensor is often held up as a gold standard, many affordable cropped sensor cameras are on the market that also perform well.
When using a pro lens (one that doesn’t compensate for the cropped sensor) the smaller sensor can only show a smaller area of the scene. Nikon labels these lenses DX (which are often more affordable and design for cropped sensors) and FX which are for full frame sensors. The effect of a cropped sensor is that it effectively multiplies the range of a lens.
For example, if you put a 50mm lens on a full frame camera, it will act as marked. But if you put that 50mm lens on a body with a cropped sensor, the effective focal range is multiplied due to the smaller sensor size. On many Nikon cameras, the crop factor of 1.5 will make the 50mm lens behave as if it is a 75mm lens. This is often referred to as the effective focal length.
The following crop factors are common:
- 1.3x This is used on some pro Canon EOS cameras.
- 1.5x This crop factor is employed by Nikon for most DX lineup, like the D7000 and D3100.
- 1.6x This crop factor is used by Canon for its APS-C bodies, like the 7D
- 2.0x Many MFT cameras like Olympus and Panasonic use this.
The cropped sensor has a few benefits that some users prefer:
- Less cost than full frame lenses and bodies.
- Less weight in general
- Ability to get tighter coverage, especially if combined with a teleconverter.
On the downside, possible negatives include:
- Less range in depth of field
- Additional math if you’re used to use the mm rating on lenses
- Low light performance is reduced.
I routinely find myself using both cropped and full frame sensors. My Nikon D600 is a full frame, while my D7000 is cropped. I also use a few Canon models that are cropped and my Olympus, Blackmagic, and Panasonic cameras all use cropped sensors.
The take-away… don’t believe the hype. There are as many good reasons to shoot on either sensor type as there are drawbacks.
Sound of in the comments below about your preferences and why.
Rich has published over 100 courses on Lynda.com. Rich has authored several books including From Still to Motion, Understanding Photoshop, Professional Web Video, and Creating DSLR Video.