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M8's photos have strange RGB elements


Kodak35

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Hello everyone, 
I've found some photos taken with my M8 had strange R/G/B, sometime Orange (or Red). It just happened with or without IR filter.

For example, screenshots from RAW.

*colors covering the scaffold:

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*water with colors spreading:

I just wondering, M8 is still great to me. Thanks for reading.

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33 minutes ago, Tux4711 said:

Hi Kodak35. Looks like chromatic aberration to me. What lens are you using?

Maybe this posting will help you: 

 

Hi, thank you Tux4711, i'm using Summicron-M 50 f.2 v4, photos taken with f/5.6.
i'm just wondering what it is, 'cause it not likes chromatic aberration much, I was tried to fix chromatic aberration but it not works ;)

Edited by Kodak35
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It's moiré. When there is very fine repeating detail in a photo and the lens is sharper than the sensor, the bayer algorithm gets tricked and the camera does not know what color to display, and so it causes a false rainbow pattern. At a smaller scale, it can cause false color artifacts around small, sharp details, which is what it is doing with the building. This is not as much an issue on high resolution cameras, as the detail has to be very fine to cause it, but on low resolution cameras without AA filters, it is often an issue. The M8 and M9 often run into this issue. There is a moiré correction tool in camera raw and lightroom, but it only helps with the color, not any patterning (not visible in this particular photo). It also has the tendency to desaturate the photo overall where it is applied, but it is better than nothing. Another option is to use Lightroom's "enhance" menu option, which uses a more computationally labor intensive raw conversion that tries to show fewer problems like this. It might help or even solve the problem. Other RAW programs like RAW Therapee offer multiple types of bayer demosaicing, and one might do better than another at suppressing it. But this is just part of the territory with the low resolution sensors. Another option is to stop down far enough that the lens gets softer, which can sometimes eliminate it....at f16 or f22 for example.

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Yes, moire was a noticeable feature with the M8 and sharp lenses. I used to see it quite a bit when I used the M8 with the excellent little 28/F2.8 ASPH (released around the same time as the M8 as the "standard" lens to go with it). It could be a real nuisance in some circumstances.  I still get problems with moire photographing butterflies using an M240 and 90 macro (and with a Nikon D810 and 105 macro). The tiny reflective scales that give the appearance of colour on a butterfly play havoc with the bayer mosaic.

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I haven't experienced Moire with an M8, but I did with a Kodak DCS760, with an earlier 6mp version of the Kodak sensor. Kodak suggested using a hot mirror filter to supress Moire. I am not sure, but isn't a hot mirror a denser version of the IR/UV cut filter? So an IR/UV cut filter may be a way to supress the Moire patterns but probably not eliminating them. One more thought. What ISO were you using?

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8 hours ago, tommonego@gmail.com said:

I haven't experienced Moire with an M8, but I did with a Kodak DCS760, with an earlier 6mp version of the Kodak sensor. Kodak suggested using a hot mirror filter to supress Moire. I am not sure, but isn't a hot mirror a denser version of the IR/UV cut filter? So an IR/UV cut filter may be a way to supress the Moire patterns but probably not eliminating them. One more thought. What ISO were you using?

I'm using 160.

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