M9 with 25mm Zeiss Biogon--Strange Magenta Artifact

[photolandscape]

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I'm seeing an interesting and undesirable artifact using my M9 with a new Zeiss 25mm Biogon--see the magenta halos around the highlights on the chrome rails of the chair in the enlargement.

 

In this shot, it is manually-coded as the 28mm Elmarit ASPH--that setting so far has given me the best results in terms of limiting red fringing and vignetting. There is a B+W UV haze filter in place. The shot is hand-held--1/80 sec., ISO 640, f/4. White balance is set manually for daylight.

 

Pls. see the two attached photos--uncropped vs. cropped @ 200%.

 

I really don't like this magenta halo-effect. Any thoughts on what could be causing it? Is it chromatic aberration? Whatever it is, how can I get rid of it?

[thompsonkirk]

That's 'fringing,' a kind of aberration that's explained here:

 

Purple fringing - Wikipedia, the free encyclopedia

 

Though yours looks red, it's a version of the above. It's hard to get rid of, because it isn't plain old CA with green on one side & red on the other - the kind you can correct easily with Photoshop: Filter>Distort>Lens correction>CA.

 

You can handle this kind by using your Magic Wand in PS, or Select>Color range, to pick out these areas & then desaturate them.

 

Kirk

[jaapv]

Using C1 as a RAW developer will reduce the problem significantly. Search the forum, it has been discussed at length.

[Alnitak]

Adobe Camera Raw will mostly remove those if you go to the lens tab and select "Defringe" and choose "Highlight Edges."