02-17-2013, 12:49 AM
[quote name='Brightcolours' timestamp='1361057777' post='21964']
Look up what "field curvature" means, the problem is that at the moment you do not know what is meant with it. Of course a lens with field curvature can have corners sharp where the center is misfocussed.
Do the two tests I suggested above.
[/quote]
I am sort of with BC here. You first need to get your centre under control. Following that you can look for how the corners behave. In addition to field curvature you can also have other "fun stuff", like tilted planes of focus or plain de-centering (e.g. one weak and 3 sharp corners). If I got correctly which lens you are having, it is a pretty early effort of Nikon to produce 24 - tele. In particular at their widest (which we are discussing here) these lenses have a lot of "fun stuff" and even prime lenses often show it to some degree.
There is a reason why there are no 24mm equivalent repro lenses. Repro lenses are typically Nikon repro lenses typically come with a 60mm equivalent focal length these days.
Look up what "field curvature" means, the problem is that at the moment you do not know what is meant with it. Of course a lens with field curvature can have corners sharp where the center is misfocussed.
Do the two tests I suggested above.
[/quote]
I am sort of with BC here. You first need to get your centre under control. Following that you can look for how the corners behave. In addition to field curvature you can also have other "fun stuff", like tilted planes of focus or plain de-centering (e.g. one weak and 3 sharp corners). If I got correctly which lens you are having, it is a pretty early effort of Nikon to produce 24 - tele. In particular at their widest (which we are discussing here) these lenses have a lot of "fun stuff" and even prime lenses often show it to some degree.
There is a reason why there are no 24mm equivalent repro lenses. Repro lenses are typically Nikon repro lenses typically come with a 60mm equivalent focal length these days.
enjoy