10-06-2011, 07:01 AM
[quote name='Klaus' timestamp='1317853784' post='12147']
The checks were done at the image center. This is hardly a valid approach to check the centering quality.
[/quote]
They did describe their charts as follows:
While decentering might not affect centre resolution, it should affect average which would put lenses off towards the lower right of the chart. There's some data points which seem to show that - still "high" centre scores but reduced average scores.
The checks were done at the image center. This is hardly a valid approach to check the centering quality.
[/quote]
They did describe their charts as follows:
Quote:The charts shows the highest resolution (at the center of the lens) across the horizontal axis, and the weighted average resolution of the entire lens on the vertical axis, measured in line pairs / image height.
While decentering might not affect centre resolution, it should affect average which would put lenses off towards the lower right of the chart. There's some data points which seem to show that - still "high" centre scores but reduced average scores.
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