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03-02-2013, 03:09 AM   #1
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What's this aberration called?

I recently bought an Olympus OM-D E-M5 and have now experimented with using old MF lenses on it. This picture was taken with the 50mm f/1.4 Super-Takumar (7 element) shot wide open. Pretty severe color aberration can be seen in the lens cap lettering. That was quite a bit reduced stopping down the lens to for example f/4 but still not completely gone.

But what is this kind of aberration called? Is this longitudinal chromatic aberration?

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03-02-2013, 03:29 AM - 1 Like   #2
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QuoteOriginally posted by Raffwal Quote
Is this longitudinal chromatic aberration?
Bingo.
03-02-2013, 03:30 AM - 1 Like   #3
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Yes, that looks like LoCA, but is incredibly severe and much more diffuse that I would normally expect. Do you have this kind of behavior with other cameras?


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03-02-2013, 03:34 AM - 1 Like   #4
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I don’t know whether it is longitudinal (aka – Axial) or transverse  chromatic aberration. Did you tried to fix it in light room? With one click you can remove most of it!! or else you have to stop down, but you loose shallow DOF!!


Last edited by Dynamo; 03-02-2013 at 05:55 AM.
03-02-2013, 03:34 AM - 1 Like   #5
arv
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QuoteOriginally posted by Raffwal Quote

But what is this kind of aberration called? Is this longitudinal chromatic aberration?
Yes, aka "bokeh fringing" (check here).

A.
03-02-2013, 03:35 AM   #6
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QuoteOriginally posted by stevebrot Quote
Yes, that looks like LoCA, but is incredibly severe and much more diffuse that I would normally expect. Do you have this kind of behavior with other cameras?
Haven't really taken a shot like this with this lens and my Pentax cameras. I'll give it a try.
03-02-2013, 03:37 AM   #7
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hi arv, I was about to send Mansurov's like!!
03-02-2013, 03:45 AM   #8
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Looks like a magenta green anaglyph 3D photo. Where are my 3D glasses?

03-02-2013, 03:56 AM   #9
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This was taken with the same lens @f/1.4 and my K20D. Almost the same, don't you think so?
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03-02-2013, 04:00 AM   #10
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QuoteOriginally posted by Dynamo Quote
Did you tried to fix it in light room? With one click you can remove most of it!! or else you have to stop down, but loose you shallow DOF!!
I only have Aperture and I don't think it has such a simple aberration removal tool.
03-02-2013, 04:07 AM - 1 Like   #11
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The DA 35mm f2.4 also has a bit of this, but only wide open. But that is quite severe. Though, keep in mind that it will not show as profoundly in all photos, depends on what you are taking photos of.
But its pretty odd that a 50mm would have this problem.
And yes, I think the newest lightroom has a tool for this kind of aberration (the older ones don't). And I don't think any other software has this yet.
03-02-2013, 04:44 AM   #12
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Really, you shouldn't be taking color photos with a black-and-white lens. Desaturate!
03-02-2013, 05:52 AM   #13
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It is very easy to remove CA in LR4. jus try the trial version...
03-02-2013, 06:00 AM   #14
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Luckily, this image is pretty much b&w, simply desaturate.
It is more difficult with more colorful images, but CA is usually most noticeable between high contrast areas. So with some care, the same solution often applies.
03-02-2013, 06:04 AM   #15
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To me the second example looks better, but that may well be becuase it isn't exposed as much. Overexposed images where there are reflective materials like this really do show it at its worst (although I don't think my S-M-C Takumar 50/1.4 is that bad). Apart from desaturing (either the image as a whole or the these specific colour channels), which often cannot be done, there's little one can to do fix in PP, so it's best to be aware of when its likely to manifest (it's also why I am much fussier about lenses that display longitudinal CA as opposed to lateral CA).

Last edited by macTak; 03-02-2013 at 06:10 AM.
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