[karlmera]

[quote name='Brightcolours' timestamp='1303201586' post='7756']

There is no field curvature worth mentioning (tested it just now). I think you may confuse some coma like effect, or more probably astigmatism, with field curvature?

Your 60mm AF-S has quite strong CA, just your camera is hiding it. Try a 3rd party RAW convertor to see how it really performs. The still quite low CA from the 55mm f2 can also be easily reigned in in a RAW convertor that allows you to correct CA, or in photoshop (in for instance the lens correction filter).

[/quote]

[karlmera]

[quote name='Brightcolours' timestamp='1303201586' post='7756']

There is no field curvature worth mentioning (tested it just now). I think you may confuse some coma like effect, or more probably astigmatism, with field curvature?

Your 60mm AF-S has quite strong CA, just your camera is hiding it. Try a 3rd party RAW convertor to see how it really performs. The still quite low CA from the 55mm f2 can also be easily reigned in in a RAW convertor that allows you to correct CA, or in photoshop (in for instance the lens correction filter).

[/quote]



Here are the 2/55UMN at f/2 and the 60mm AFS at 2,8, both at 1:1.

[Brightcolours]

Real.y curious results you get....



Here is my 55mm f2 at about 1:2.1:





And at 1:1.45:





The slight unevenness is fault of the book page not being totally flat and of very thin paper.

As you can see, my 55mm f2 have no field curvature to speak of.... at least not anywhere near the curvature you are getting!

[karlmera]

[quote name='Brightcolours' timestamp='1303400297' post='7817']

Real.y curious results you get....



Here is my 55mm f2 at about 1:2.1:





And at 1:1.45:





The slight unevenness is fault of the book page not being totally flat and of very thin paper.

As you can see, my 55mm f2 have no field curvature to speak of.... at least not anywhere near the curvature you are getting!

[/quote]



Very interesting! Did you use a DX camera?

[Brightcolours]

[quote name='karlmera' timestamp='1303401520' post='7820']

Very interesting! Did you use a DX camera?

[/quote]

Well, DX is weird Nikon speak <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />... I used a Canon APS-C camera (22.2mm wide sensor, a tad less wide than the one in your D300).

[karlmera]

[quote name='Brightcolours' timestamp='1303401967' post='7821']

Well, DX is weird Nikon speak <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />... I used a Canon APS-C camera (22.2mm wide sensor, a tad less wide than the one in your D300).

[/quote]



Here 2 tests on FX, 2/55 and 60AFS, both at 1:1.

[Brightcolours]

[quote name='karlmera' timestamp='1303407189' post='7822']

Here 2 tests on FX, 2/55 and 60AFS, both at 1:1.

[/quote]

I have the suspicion that you pushing it to 1:1 (I can't go past 1:1.45 at the moment) is the culprit here. On FF I see almost no field curvature at 1:2, and I start to see more at 1:1.45.



If that suspicion is correct, then this lens is best used close to its designed focus distance, to get most out of it. I will not be in a position to test it reversed (nor is 28mm f1,8 brother) for quite some time still.





ps: I can't show the FF results, as I checked through the viewfinder of a film SLR.

[karlmera]

[quote name='Brightcolours' timestamp='1303408041' post='7823']





If that suspicion is correct, then this lens is best used close to its designed focus distance, to get most out of it.

[/quote]



Yes, I think this lens has its best results at 1:4. Unfortunately I can only get 1:3 with a thin adapter because of the FFD of Nikon. Reversed on FX at 4:1 here at f/2, f/2,8 and f/4.