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This is a question mostly to the PZ masters
Based on a recent query asking about reproducing flat objects is there a way to extract field curvature info from the lens reports?
I understand current PZ testing removes that from the data by repurt "best observed" which might be in different focus positions. For centre, boarders and extreme boarders. While this is fine for many tasks it is not good for the task at hdnd.
If it is not included adding it to future reports might be something to consider.
Thanks.
J.
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[quote name='joachim' timestamp='[url="tel:1333174014"]1333174014[/url]' post='17203']
This is a question mostly to the PZ masters
Based on a recent query asking about reproducing flat objects is there a way to extract field curvature info from the lens reports?
I understand current PZ testing removes that from the data by repurt "best observed" which might be in different focus positions. For centre, boarders and extreme boarders. While this is fine for many tasks it is not good for the task at hdnd.
If it is not included adding it to future reports might be something to consider.
Thanks.
J.
[/quote]
This is difficult ... As you may have guessed ;-)
In theory the info could be extracted from the EXIF data.However, this assumes ...a) that the EXIF data has a sufficient granularity regarding the provided focus distance datab) that there is only a minimum centering defect ( which has an impact on the focus point )
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03-31-2012, 05:18 PM
(This post was last modified: 03-31-2012, 05:19 PM by joachim.)
[quote name='Klaus' timestamp='1333194329' post='17212']
This is difficult ... As you may have guessed ;-)
In theory the info could be extracted from the EXIF data.However, this assumes ...a) that the EXIF data has a sufficient granularity regarding the provided focus distance datab) that there is only a minimum centering defect ( which has an impact on the focus point )
[/quote]
Hi Klaus,
Thanks. I had to laugh when reading your answer. I feel as clued as before.
Just for an idea or another laugh: Would/could the difference in MTF between best boarder (what you publish now) and the boarder reading when the centre is best be a measure to indicate the quality of field flatness? I assume that could be reasonably easy derived from the data you take. Still the centring issues would remain ...
As I said: Thanks for replying and the above is an idea not a request.
Best wishes
Joachim
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[quote name='joachim' timestamp='[url="tel:1333214336"]1333214336[/url]' post='17233']
Hi Klaus,
Thanks. I had to laugh when reading your answer. I feel as clued as before.
Just for an idea or another laugh: Would/could the difference in MTF between best boarder (what you publish now) and the boarder reading when the centre is best be a measure to indicate the quality of field flatness? I assume that could be reasonably easy derived from the data you take. Still the centring issues would remain ...
As I said: Thanks for replying and the above is an idea not a request.
Best wishes
Joachim
[/quote]
Actually I did that in the Samsung 16mm review. :-)
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[quote name='Klaus' timestamp='[url="tel:1333269888"]1333269888[/url]' post='17248']
Well, this is the only NX lens with a severe design flaw so far.
[/quote]
If I recollect u also displayed extra info (diagram) on this topic re: the Zeiss 28mm review.
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