Does everyone agree with P. J. that such purple "bloom" (or whatever it
is called) will be seen normally with any lens (emphasis) on a digital
sensor? Even "digital" lenses will do this? Should one never shoot a
dark subject out of focus against a light background?
Serious question: Please help.
Thanks,
Joe
P. J. Alling wrote:
That's not CA that's bloom, a characteristic of the sensor not the lens.
You will probably see it to a greater or lessor extent with any lens on
a digital sensor.
Joseph Tainter wrote:
Sorry to say, I have just seen my first chromatic aberration from
this lens. In Prague a couple of weeks ago, I photographed some
gargoyles on a cathedral. The scene was an individual gargoyle, shot at
210 mm. and f5.6 (wide open). In the background are some gothic
architectural elements that are rendered out of focus, set against a
lighter sky. There is a purple halo around the OOF architectural
elements. Since the CA is in the center of the image area, ACR cannot
fix it. Although shot wide open, the gargoyle I was focusing on came out
pleasingly sharp.
So now I am thinking again about the DA 50-200. But I believe I
have seen an image with CA from this lens, too -- a white license plate
rendered purplish. Again, it was in the center of the image.
Still, this is the first time that the SMC F 70-210 has failed me,
and this was a limited situation. So for now I will keep using it. I am
waiting to hear the details of Pentax's forthcoming D FA "high
performance telezoom."
I sure wish I could put my hands temporarily on a DA 50-200 to test
it systematically against the F 70-210.
Joe
