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Very interesting to hear your about your findings .
sebboh wrote:
"that amount" meaning what you show in the examples? i haven't seen much of that either, but easily noticeable i've seen lots of. out of curiosity what primes have you used that don't show loCA?
Frankly , no primes that I can think of, there is always a chance of loCA , in my limited experience .
I've hardly ever seen it with large format lenses, but that's a different topic, I guess .
'That amount' is what I see in the examples; in the focus plane .
More on that below .
Bifurcator wrote:
I don't think it's off topic. (I think) the entire reason to have a image thread on a lens or lens group is to discuss how to use them, convert them, what their strengths and weaknesses are, and of course to brag a little. So you seem perfectly on-topic to me.
Bifurcator wrote:
And with that, I'm as confused as you are. I have a couple of hundred MF lenses and only a handful produce CA artifacts that show up in 100% screen displays.
A couple hundred ? Mate, you really like your MF lenses !
Thanks for the samples .
sebboh wrote:
i agree with you about lateral CA on in focus regions being generally not a serious problem, but loCA, or bokeh CA, or lateral color, or whatever it's called is prevalent in most of the lenses i've used. to be specific about what i'm talking about it's the purple fringing in the oof regions in front of the focus and green fringing in the oof regions behind the focus point
.....but i see it to some degree in every narrow dof shot i've taken with a lens faster than f/2 and in every narrow dof shot i've taken with a telephoto that wasn't a zoom or apo....Show more →
As for the latter part : With the Minolta MF lenses I've tried on the Nex, the difference between zoom lenses and primes I can see re. loCA is that the zooms actually do worse, but I'm assuming that's because the few I tried do worse in every respect , like resolution, flare and sharpness .
Also, the slower MF lenses don't do any better than the faster ones in my case; wide open, I'm getting PF, two stops down, it's fairly well controlled, no matter if the widest aperture is 1.7 or 5.6 .
Now here is what confuses me quite a bit: the magenta/green shift you mention, which is typical for longitudinal CA, is moved to the back with all my lenses .
See the images below :
A : focused on the hinge, PF on the focus point
B: hinge is (mis)focused to exactly the point of color shift between magenta and green fringing, which is further back
Hence, the color neutral area lies well behind the focus plane !
I can easily see the fringing change colors on the display.
I wished I could try my Minolta lenses with a different digital camera, or even another Nex .
(I hope I'm getting my terms right - foreign speaker ....)
http://img820.imageshack.us/img820/7374/shafftest.jpg
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