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07-24-2009, 10:36 AM   #16
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QuoteOriginally posted by inwonderland Quote
- Many of these were shot wide-open (I've posted a link to a much better image gallery w/ details of each shot)
- I am using a UV filter and lens hood
I agree with X-man, first thing I would do is to remove the UV filter. I'm seeing on your samples an inexpected amount of Bokeh CA. I have the D-FA 100mm macro and that's a defect I don't remember seeing. I may try some shots with the same chart later to compare with your shots.

07-24-2009, 05:05 PM   #17
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QuoteOriginally posted by gofour3 Quote
I have been shooting mostly slide film since the early 70’s, using older Pentax K series equipment and have never come across this purple fringing issue. So it must either be a digital or newer lens issue??.
Did you pixelpeep back then?
After scanning slides with my Nikon 9000 scanner I can see fringing in many lenses on many subjects if I pixelpeep. Fringing is just as visible on film as on digital, but in pre digital age we had to use a microscope to get the same magnification pixelpeepers now routinely scrutinize their images under. It was't seen as important then...and isn't now....
07-24-2009, 08:44 PM   #18
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QuoteOriginally posted by inwonderland Quote
Thanks to everyone for your comments.

- Many of these were shot wide-open (I've posted a link to a much better image gallery w/ details of each shot)
- I am using a UV filter and lens hood
I shoot macro shots all the time with the FA 50mm and FA 100mm. The FA 100mm will exhibit some chromatic aberration on high contrast subjects, including minor purple fringing, wide open. Almost all of the CA goes away by stopping down one stop to F4. Note that the CA is visible only on high contrast targets wide open; most photos don't show it.

Also, get rid of the UV filter. You certainly don't need it, especially with the 100mm D-FA.

Finally, just as tip, it really helps if you don't strip out the EXIF data from your posted photos; if you do then we have to ask a bunch of basic questions (like what f-stop you are using) rather than you giving us all the info that we need in the photo.

BTW, your color profile for some of these images as listed as "Color LCD" which should not be the case. You should make sure that anything you upload for viewing on the web (as opposed to an ICC-compliant program) is converted to sRGB color-space.
07-24-2009, 09:12 PM   #19
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QuoteOriginally posted by Pål Jensen Quote
Did you pixelpeep back then?
After scanning slides with my Nikon 9000 scanner I can see fringing in many lenses on many subjects if I pixelpeep. Fringing is just as visible on film as on digital, but in pre digital age we had to use a microscope to get the same magnification pixelpeepers now routinely scrutinize their images under. It was't seen as important then...and isn't now....

I don’t own a scanner and I rarely get any slides scanned in a lab . I do view my slides on a projector and have never noticed any fringing. Same with any enlargement I have made up to 24” x 36”.

I guess I’m just happy to be stuck in the 70’s.

07-24-2009, 10:20 PM   #20
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Some thoughts about these CA effects on the examples.

When I saw the image with the examples on the leather jacket, I was reminded of the photozone.de test of the 200mm lens. In that test, there is a discussion of Longitudinal Chromatic Aberration and how that will give a color gradient to items that are front or back focused.

I did a little more reading and I have found an interesting wiki article that talks even more about CA and how to identify the major types and what the differences between digital (CCD and CMOS) and film.

Chromatic aberration - PanoTools.org Wiki

It seems to be a pretty good read and helps to put some of the questions about purple fringing at rest (at least for me).
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