DX format vs FX format: what you need to know about Nikon’s sensor sizes

DX format vs FX format: what you need to know about Nikon's sensor sizes

Discover which Nikon lenses work with which sensor formats in our DX format vs FX format comparison.

DX format vs FX format: what you need to know about Nikon's sensor sizes

Nikon makes DSLRs with two different sensor sizes: FX and DX. FX sensors are the same size as 35mm film, but they are more expensive to make. This is why most enthusiasts use the smaller DX-format models.

The DX format sensor is about the same size as the old APS-C film format – in fact, these sensors are sometimes referred to as ‘APS-C’ format.

To go with these sensor sizes, Nikon makes both FX and DX lenses. FX lenses fit on both types of camera, but are often large, heavy and expensive.

DX format lenses are solely for cameras with DX-format sensors. They project a smaller image circle to cover the smaller sensor, but they’re lighter and cheaper.

If you have a DX-format Nikon, DX lenses are the most cost-effective buy, but if you plan to move up to the FX format, you’ll need to swap over to FX lenses.

SEE MORE: 100 Nikon DSLR tips you need to know right now

Nikon DX format vs FX format: learn your lenses

Nikon DX format vs FX format: focal factors

DX format vs FX format: 01 Focal factors
DX sensors capture a smaller field of view, so it makes it appear as if you’re shooting with a longer focal length lens. This is called the ‘crop factor’, and you need to multiply a lens’s actual focal length by 1.5 to get its effective focal length on a DX camera.

Nikon DX format vs FX format: DX lenses

DX format vs FX format: 02 DX lenses
This DX-format D5200 comes with an 18-55mm kit lens, but the 1.5x crop factor means the lens is effectively a 27-82.5mm one, which is a typical ‘standard’ zoom range for a D-SLR. This is a DX lens which only covers the DX sensor area, so it’s not suitable for an FX camera.


Nikon DX format vs FX format: FX lenses

DX format vs FX format: 03 FX lenses
This FX-format D610 comes with a 24-85mm kit lens. 24-85mm is the lens’s effective focal length because it’s on a full-frame camera (the crop factor is 1.0). You can use it on a DX Nikon, but it will be too ‘long’ to be a useful standard zoom, with an effective range of 36-127.5mm.


Using the DX format crop mode

Using the DX format crop mode
You can use DX lenses on FX bodies in DX ‘crop’ mode. This uses only the central part of the sensor and sacrifices much of the camera’s resolution.

Final Tip
Consider buying FX lenses for a DX-format body, in case you swap formats in future.


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  • 1goodbob

    I can see the difference between the two on paper & the Specs. I also think that on many cameras, If you are not enlarging pictures more than 8×10 prints, the superior system may not be evident.

  • Some Dude Named Lee

    There is no such thing as an “effective focal length.” There is only an “effective field of view.” A 50mm lens is still a 50mm lens…it’s not possible to change that unless you use a teleconverter.

  • paul croasdale

    So, just to confirm… On a DX body, an 18mm FX lens AND 18mm DX lens have a field of view effectively the same as a 27mm on an full-frame body. So the ‘crop factor’ (FOV-factor is a better term, IMO) is a function of the sensor ONLY.

    To me, it seems intuitive to assume that the DX lens on a DX body wouldn’t involve that 1.5x factor. But that’s not the case, correct?