The Difference Between DX and FX Nikon Camera's

Everywhere on forums and different blogs people are asking what the difference between a FX camera+lens is to a DX camera+lens. The answer is pretty simple and if you want to know and see examples, then continue reading.


DX and FX refer to the size of the image sensor within the camera, DX is smaller than FX, about 1.5X. It also refers to the different lens types, DX lenses have an opening that will only completely fill a DX sensor with light but will not fill the complete FX sensor. See crapy paint picture below




Now that that is out of the way, we should understand that a DX lens on a FX sensor will end up with the sensor only being partially exposed to light, leaving the rest black.




Now on the other hand, when using a FX lens on a DX sensor you wont get the full image because the sensor isn't big enough in dimensions compared to the lens opening.



Here is a example of a 80-200mm FX lens zoomed at 200 on a FX camera



And now the same lens, same positioning, but on a DX camera





As you can see using a DX sensor gives you a false zoom. Since the crop is 1.5x we can say that the apparent focal length of a 200mm on a DX camera is actually 300mm

Some may think this is better but it really isn't, the quality difference is enormous and using a FX sensor is just like a piece of film.



Hopefully that helps you understand the two sensors. If you have any questions or see something I did wrong let me know! :)