10-17-2013, 02:23 PM
f/1.4 is always focal length divided by 1.4 and will result in a different aperture diameter depending on focal length, no doubt. And it will result in some problems for lenses at wide aperture, or how do you explain the price difference between Zeiss 55/1.4, Nikkor 58/1.4 and Nikkor 50/1.4? It's just the different approaches to get rid of that problems. And all I was saying is, that a Sigma 35 at open aperture is sharper and shows less CA than a 85/1.4G which is a bit hard to understand in aspects of price class.
And also no doubt that fast lenses do nearly always show the problem of CA and of color fringing. Question remains how good this 58 is in that aspect.
Then, masking of information which is in the picture needs to reduce the amount of the information in the picture and is therefore a loss of information. Maybe it's my mistake to set "information" equal to "quality". Corrected CA is better than uncorrected CA but still worse than no CA from the source, in that case the lens. If I mask the purple or green shadows of lines away, the result is less contrast because I switch off some information which was in the picture, but due to optical failures on the wrong place.
"Bokeh is how it is" - point taken, I agree and was not disagreeing on that before.
Now, let's wait until we see the first lens tests which should show if Nikon did a good job or is just asking too much money.
And also no doubt that fast lenses do nearly always show the problem of CA and of color fringing. Question remains how good this 58 is in that aspect.
Then, masking of information which is in the picture needs to reduce the amount of the information in the picture and is therefore a loss of information. Maybe it's my mistake to set "information" equal to "quality". Corrected CA is better than uncorrected CA but still worse than no CA from the source, in that case the lens. If I mask the purple or green shadows of lines away, the result is less contrast because I switch off some information which was in the picture, but due to optical failures on the wrong place.
"Bokeh is how it is" - point taken, I agree and was not disagreeing on that before.
Now, let's wait until we see the first lens tests which should show if Nikon did a good job or is just asking too much money.