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Red Edge - Red Middle?


TacTZilla

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I've seen this on bright specular highlights such as sunlight on water or wet beach sand in sunlight. If you zoom into the image is the pink coloration uniform in the shadows and mid tones or only where there's a bright highlight of the sun reflecting from the wet path? It could also be a form of moire which only shows up on fine detail in the area where the lens is focused.

 

If it's only the highlights I believe people have been successful in removing it with the purple fringe reduction feature in Capture One.

 

Bob.

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There is something going terribly wrong in that picture. When I saw that photo my mind flashed on the first sample pictures from the Kodak 14n.

 

These are still on line at Kodak Japan for some reason -

 

Kodak Professional DCS Pro 14n

 

A 100% crop of the highlights in water has a similar broken up look to the color but isn't confined to one part of the sensor.

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This, Alan, is different. It is edge colour shift at the high-contrast edges during Bayer interpolation. It varies per RAW converter, but it is governed by contrast and lens. The higher the microcontrast of a lens the worse it is. It is comparable to - but not identical to- moire. The best remedy is to

a. use C1

and

b. use the colour replacement brush to correct, as Steve suggested.

 

It is interesing how the colour of the artefact shifts with the focus in the image I posted in the other thread. In front: red. In the plane of focus: magenta. And back of the focus: blue. Bob's image shows this effect as well.

That alone proves that it is not a sensor-bloom type of occurrence.

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I know it looks different, and the cause is probably different too. I wasn't refering to how the color shifts across the sensor - that is very different. But the way the highlights get broken up into pixelized spots was familiar. Both images show a lack of some kind of basic issue or a processing problem. I'm not qualified to say what other than each company missed it. (Or Kodak missed both.)

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Well, both the Kodak camera (with a FillFactory sensor), and the M8/M9 with a gen-u-wine Kodak sensor, lack AA filters, and I'm sure moire is a factor in both images, which is why the sense of deja vu. Other factors like a touch of blooming and fringing, or the RAW converter, no doubt play roles, too. In other words, Jaap and Alan are both mostly right.

 

In Bob's picture, I'd say the red/magenta band is quite literally showing the DoF - the area of the path where the images of the pebbles are sharp enough to create an interference pattern and some moire/color fringing amidst the pixels. In front of or behind the band, the image is just fuzzy enough to act as its own moire filter.

 

(BTW the reason the tint is magenta is because the red and blue pixels are more widely separated than the green pixels, so they get "confused" faster by fine details/textures. Red + blue = magenta.)

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Well, both the Kodak camera (with a FillFactory sensor), and the M8/M9 with a gen-u-wine Kodak sensor, lack AA filters,...

 

Lack of an AA filter certainly could be a big factor but there are other cameras that don't have AA filters and I think they would work fine in a similar situation. And moire is defined as an interference pattern and these subjects are all random and the color "dots" look like high speed film grain or a magnified stochastic printing system just in the sharp highlight area. Then look smooth and normal elsewhere. I think the image processing is totally breaking down in these areas and is just generating something to fill in. This almost has to be a processing anomaly almost like an effect you'd generate in Photoshop. I almost could understand issues appearing on the 14n as that was so early in the digital camera era. (Although Kodak had a lot of experience by then.) But 8 years later?

 

Boy am I out of my depth here. Somebody at Leica who really knows what is going on and how to fix it will have to step up to the plate. I haven't a clue... between the sensor, the IR filter, the micro lenses, the image processor, the firmware, there's a lot going on.

 

Even desaturated, it doesn't look right. So it is not just a color problem.

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another example. Shot into the light (lux 50 ASPH f5.6) and seems to happen with highly reflective dark surfaces. Is worse when viewed in LR2.6

 

 

 

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Guys, can anyone of you that have the C1 software process it with this one instead? Which processor are you using Bob? Reason for this is that sometimes me too, I have seen color fringing on reflections, but when I process on C1 it goes away. Of course I don't have the M9, and your'w is a lot more severe, but still...

And it's all in water reflections. Both yours and mine

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Hi.

 

No IR filter here.

 

I import using LightRoom, but I open in and use Photoshop CS4.

I was hoping to swap to using LR all the time, but find myself using PS because I'm used to it.

 

Don't want to sound like a dumb ass, but whats C1 :o Duh!

 

B

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