06-16-2011, 09:16 AM
[quote name='mst' timestamp='1308213070' post='9283']
Actually, I see yellow/blue CAs quite often in the test charts. And not only with Nikkor lenses.
In addition, CAs (laCAs) don't necessarily increase proportionally with distance from the image center. In fact, with many lenses they don't.
-- Markus
[/quote]
I said it is quite rare (after it was being said it most often is) and that you more often see red/greenblue or magenta/green... not that one does not encounter it?
CA's do increase proportionally with distance from the center, just not always totally proportionally. In the center one never will see it (unless the lens would have serious decentering issues I guess.
I did write that some don't have a nice and gradual CA shift, though, making the CA not so well correctable (but them one can mask it still to get rid of the coloured edges). We do not disagree here.
Actually, I see yellow/blue CAs quite often in the test charts. And not only with Nikkor lenses.
In addition, CAs (laCAs) don't necessarily increase proportionally with distance from the image center. In fact, with many lenses they don't.
-- Markus
[/quote]
I said it is quite rare (after it was being said it most often is) and that you more often see red/greenblue or magenta/green... not that one does not encounter it?
CA's do increase proportionally with distance from the center, just not always totally proportionally. In the center one never will see it (unless the lens would have serious decentering issues I guess.
I did write that some don't have a nice and gradual CA shift, though, making the CA not so well correctable (but them one can mask it still to get rid of the coloured edges). We do not disagree here.