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Has anyone seen something similar? I am referring to the red edge on the left side of the wood post in the attached cropped photo. Taken with Cron 28 ISO 320.

 

Thanks,

Alan

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It reminds me of this red/purple fringing at the edge of high contrast areas with strong highlights that I saw in a DNG file posted at outbackphoto.com

 

Leica M8 Experience

 

I have not seen it in any of my pictures.

 

Furrukh

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Guest lykoudos

Hello Alan and Furrukh,

 

Cordially welcomely in the forum Alan. Your two views of the different details of our next environment please me very well. They are not no more noticed unfortunately in the normal everyday life by us in such a way. Separate we hurry ohless past. We leave unused opportunities to deepen us even into larger connections. Because in the small and particular a whole is contained. Thank you for these pictures.

 

Kind regards

 

Wolfgang (Leica MP grey hammertone)

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Looks like chromatic aberration to me.

 

This can be correct in many raw processors. Check out the lens tab in ACR.

 

Thanks Scott, I tried 'reducing fringe' in Lightroom but could not get rid of it (maybe 50% better). Don't know how to do it in C1 LE.

 

I am going to shoot the same scene tomorrow with different lenses to see if it's the lens or the M8.

 

Alan

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is this really a problem for you ? I mean in the old analog photo times, you get your photo from the lab and everything was OK. Now your are sitting in front of your computer and crop and crop and crop untill you can find something we had to discuss :)

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Thanks Scott, I tried 'reducing fringe' in Lightroom but could not get rid of it (maybe 50% better). Don't know how to do it in C1 LE.

 

I am going to shoot the same scene tomorrow with different lenses to see if it's the lens or the M8.

 

Alan

 

It will probably reduce if the posts were in focus. Right now it is an out of focus highlight

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Interestingly I have a similar problem with the Canon 5D where there are bright (but not overexposed) edges of buildings. It doesn't seem to be the same as normal chromatic aberation. The fringe is red, not purple or green. I have 5D shots which show normal purple/green fringing which can be corrected in ACR as well as the red fringe which is more difficult to fix.

 

It seems to be related to digital since I've never seen it on film.

 

Bob.

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is this really a problem for you ? I mean in the old analog photo times, you get your photo from the lab and everything was OK. Now your are sitting in front of your computer and crop and crop and crop untill you can find something we had to discuss :)

 

I apologize if I am wasting space on this forum or anyone's time. Don't know which topics are acceptable here, since I just joined this forum. However, this is quite visible on my screen without cropping (8x12 inches), and totally bad at 1:1. I just "crop, and crop, and cropped" in the attachment to make it easier to see for the posting.

 

Just wanted to know if this is the lens or the camera. Thanks to Bob, it appears to be an artifact of digital photography.

 

Alan

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This fringing can be seen in most, if not all, digital cameras where you have a very bright line next to a dark backround, or vice-versa. It's the camera, not the lens (or rather, it's the sensor.) There are specific clean-ups for it in various software packages. If you want to see it in its most notorious form, take some pictures of dark bare tree branches against a bright sky (under-expose the branches, so they are silhouetted.) The fringing is usually purple or red.

 

JC

 

Edit: for clean-up, for example, see in Lightroom under Camera Calibration > Lens Correction > Reduce Fringe

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I apologize if I am wasting space on this forum or anyone's time. .................

Alan

 

Welcome to the community. Olof has a smiley at the end of his post so you're safe. :D

 

I think most fixes/photoshop actions for it involve identifying object edges with a high pass filter, expanding and feathering the selection slightly and then desaturating the red (or whatever color the fringe is) channel within the selected area.

 

Bob.

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Hi Alan,

 

You might have to manually do what Robert has outlined above. You are right your fringing is too strong to get rid of by using automated procedures. I tried using Lightroom’s and other tools to get rid of the fringing in the file I posed above (when it first appeared at outback) in this thread and was not able to get rid of it; it clearly showed in 8 by 10 prints. I was only able to get rid of it in Photoshop by using steps similar to the ones outlined by Robert.

 

Good Luck!

 

Furrukh

 

N.B. Olof did have a smiley in his post; I don’t think he meant any harm :)

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The problem here is that there are at least 5 sources for colored edges or fringes in digital pictures, and people tend to get them confused. And they cannot all be corrected - or corrected by the same method.

 

1. Lateral chromatic aberration in the lens. Things closer to the edge of the frame tend to get red and cyan fringes on opposite sides. Due to the lens acting like a prism and projecting a red image that is slightly larger or smaller than the blue/green images. Usually easily correctable in Adobe Camera RAW and I assume other RAW developers - or with PhotoShop CSII's lens correction filter (although doing it in RAW before the pixels have been "crystallized" into an image works better, IMHO).

 

I think this is what Alan is showing in his wooden posts, but perhaps not. I have preset corrections for each of my lenses saved so that I can apply it with a click in Adobe CR.

 

2. Longitudinal chromatic aberration - the lens focuses the red image (or blue image) at a different point than the other colors, leading to a color fringe of one color all around the subject - essentially a red or blue blur around things. This is harder to correct, since shifting the offending channel in RAW won't work (the fringe just gets bigger on one side as it gets smaller on the other).

 

3. Micro-lens induced chromatic aberration - the microlenses over the pixels start to do a prism thing with the incoming light at strong angles. Shows up in some full-frame Canon shots, and would be a real issue with the M8 except for the offset microlenses. Usually correctible by the same means as lens-based lateral CA, since it is essentially the same problem occuring via a different part of the optical path,

 

4. Blooming - spillover of electrons from an overexposed photosite into surrounding photosites (pixels). Which is what shows up in that car chrome image above. Also shows up around overexposed windows in indoor shots. It is USUALLY blue or purple because that is the most energetic part of the visible spectrum, and thus most prone to overexposure and overflow. Difficult to correct unless it is very minor.

 

5. Color edge moire - also visible in the car shot in the chrome strip above the car door. red and cyan barber-pole stripes as the bright chrome strip crosses red/green or blue/green pixel pairs. Sometimes a gentle dose of color noise reduction will make it go away by blurring the obvious colors into the surrounding black and white.

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Unfortunately, DxO Optics does not currently support the Leica M8 and its lenses. If it did, prettty much all of the optical problems listed would automatically be eliminated or greatly minimized. I've been using it for about two months now and couldn't work without it at this point. It is simply amazing how much better my images look when all of the distortion, vignetting, and various chromatic aberations are corrected. Additionally, the DxO lighting effects and highlight recovery get the most out of the camera's dynamic range and can enhance the shadow detail in ways that were not possible for me before. (Without supplementary lighting.) I know that the Leica firmware must automatically do some of this too. But it isn't the same.

 

Leica lenses are great, but no lens is perfect. These days the photograph is produced by a combination of lens, camera, firmware and raw conversion software. All I can say is if you can get DxO to support the M8 you really will unleash the potential of that camera and its lenses. (I have over 3 years experience using C-1 to convert thousands of images, and it doesn't come close.)

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Thanks Andy, extremely educational for this newcomer to the world of digital photography. I've been boning up on processing RAW files but it will be a while before I have enough knowledge to use all the suggested software. Only tried C1LE and Lightroom so far using their more rudimentary functions.

 

Interestingly I just found the thread Official Leica Statements in which Leica was quoted :

 

"Absence of color fringing / Image Resolution

The extremely thin layer of the filter, 0.5 mm prevents color fringing at the corners of an image. This phenomenon, which is also known as astigmatism and is frequently encountered with digital SLR cameras, is not a problem for the LEICA M8 because of the thin glass cover on the image sensor. This feature, plus the particularly high imaging quality of Leica M lenses, is the reason for the high corner-to-corner image resolution."

 

Alan

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"Absence of color fringing / Image Resolution

The extremely thin layer of the filter, 0.5 mm prevents color fringing at the corners of an image. This phenomenon, which is also known as astigmatism..."

 

 

As many others have previously pointed out, astigmatism is a different lens fault.

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