| Joined: | Sun Apr 1st, 2012 |
| Location: | South Lakeland, UK |
| Posts: | 4066 |
| Status: |
Offline
|
Thankyou gents for that info.
I'm not sure what is meant by DX and FX,could you pls explain.
FX is almost the same as the original 35mm film frame size, 36 x 24mm, DX is smaller, 24 x 16mm.
http://www.nikonusa.com/en/learn-and-explore/article/g588ouey/the-dx-and-fx-formats.html
If you use any given lens on a DX camera you get the effect that the lens is 'longer' (by a 1.5 multiplier) than that same lens would be on an FX camera because you are only using a smaller part of the available image.
'DX' lenses are exactly the same focal length as they state but make a smaller image circle and don't cover an FX sensor with their image. DX lenses tend to be cheaper.
So an FX lens can be used on both FX and DX cameras but DX lenses will only produce an image with a dark surround if used on film or an FX camera which is locked to FX (FX cameras can turn off the surrounding pixels automatically when a DX lens is fitted but it's only a partial frame).
Given that a DX camera only uses the centre of an FX lens image circle, if that lens suffers from vignetting or soft edges then those impediments won't spoil your photograph. So you can get away with older possibly slightly inferior lenses because you are only using the good, central part of the image.
____________________
Robert.