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Old Oct 13, 2012, 04:47 PM
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Dance the skies...
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United States, MA, Walpole
Joined Dec 2003
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Quote:
Originally Posted by FlyingPanMan View Post
Hiya All,

First posting here because I just bought two 808#16's V2 with D Lenses and think they are t'riffic!

I'm in the UK and have been using one in my motorcycle helmet with a power pack while riding (see my YouTube channel in my username). I know there are still problems with these units and know about the blue-grey shift. I've just come across something that you may be able to duplicate. I have the Windows "Classic" desktop colour scheme on my computer monitor and I was messing with the camera shooting the screen, which was predominantly blue desktop.

When replaying, the scene surrounding the monitor screen went all orange and took ages to recover. It was in flourescent (modern energy saving bulb) light but the awb setting was auto, contrast low, saturation higher, colour normal, exposure dark. I have the latest firmware and software installed and was able to replicate the problem on my other camera.

Haven't got any photos unfortunately, but I thought the info might throw some "light" onto the problem. In any case, perhaps shooting plain background monitor screens of various colours may be of help in diagnosing the colour shifts.

Cheers, Paul.
The color shift cause is pretty well established, Paul. It's the camera's auto white balance sensing essentially nothing but one color (e.g. blue) and forcing the image to go to a neutral white balance (i.e. shades of gray) with the appropriate additive color(s). In the case of pure blue, yellow is the additive color needed to make gray. It may seem illogical, but to get yellow on our monitor display, it requires combining red and green pixels together, with no blue! If the blue is not pure blue, then the additive colors needed to make it look gray could be more red than green, creating an orange hue to the scene on your screen outside the monitor display. I've demonstrated the gray shift using a pure green screen as well.

One solution is to have a fixed white balance setting, such as the "Daylight" setting (but maybe calling it "Sunny" to go with the "Cloudy" setting) that locks the color balance to look like a "good" auto WB setting (if one could be agreed upon by a majority of users). I think we may get to that point when final tweaking of the color toggles is tackled by the developer. But then, if shooting during a day that has both sunny and cloudy periods, the color balance may actually be worse when the lighting changed to cloudy with the Sunny setting selected than it would have using the Auto WB setting.

Auto WB does a pretty good job, and another solution is to always try to keep the scene with multiple images, colors, contrast, etc. in it (e.g. don't shoot a pure blue sky... keep a bit of ground in the scene). This is not a perfect solution either since you can't see what is being recorded. But you can just trim out any unwanted color-shift portions, or even correct those sequences via post-processing by adding the proper additive color(s) manually with a capable editor if none of these double-edged solutions work for you.
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