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February 26th, 2004, 02:38 PM | #1 |
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Can't get the colors right in ambient light...
I encountered this annoying (and constant) color fidelity problem: It was a winter day at noon, overcast (and the sun behind the clouds was relatively low here at 65 degrees north), snowing, almost no shadow and lots of snow on the ground. I then tried to shoot a yellow brick building in ambient light. No matter what I did, the yellow bricks had a slightly too warm tone.
My camcorder (Sony PDX10p) is a quite limited one, because it has only "indoor" (3200 K), "outdoor" (5800 K), "auto" and "manual" white balances. When I used the 5800 K setting, the picture was slightly too warm. The same with auto mode. I even tried to set the whitebalance from the snow ( < 100 IRE ) with no success. Still too warm colors on bricks. I tried to apply white balance shift from the "custom presets" menu of my camera. I did not notice a big change. I suspect I need to apply a more powerful transformation... Or am I doing something wrong here? Oh, I allmost forgot. I did use a Hoya multicoated HMC UVA+UVB+IR filter that has a local reflection maximum of +0,5% (reaching 1% reflection if I remember it correctly) somewhere at the red end of spectrum, but that shouldn't be a problem - or is it? The questions: 1) What could I do to compensate this inadequate set of white balance presets? 2) Any ideas on how to calibrate the camcorder (or recording) and get more natural color? 3) Does anybody know how much (in Kelvin) the white balance shift steps in the Sony PDX10 are? These color fidelity problems repeat and repeat and repeat and it seems to be impossible to achieve natural reproduction of colors... - - I was happy with my camcorder until I saw what a professional 6000 euro still camera can do... Sony says my camcorder is a pro model, but I would call it "pro" instead... - - |
February 27th, 2004, 03:04 AM | #2 |
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I don't know your camera but that filter might definitely affect
things. I would test that out first to see if that's the problem. If not, then you've at least ruled that out. Does this happen all the time or only with that "scene"? If so, you should be able to fix the problem in post with color correction tools. Just a thought. I'll let others handle the questions regarding the exact working of the camera.
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February 27th, 2004, 08:19 AM | #3 |
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Just a guess here, but i think, because of the structure of snow, they actually reflect a bit of extra blue, especially on a clear day when the sky gets refracted through the snow crystals. If you white balance on that - the effect would be the same as using a warm card.
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March 2nd, 2004, 06:43 AM | #4 |
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This is a general problem. I have had trouble recording "correct" deep greens, too. Too little saturation although it's a 3CCD cam...
Fixing the colors in post is a bit difficult if one doesn't know what to fix and to what extent. Thus a comparison picture is needed but that is the exact same picture as one needs to correct... Unfortunately I am not experienced enough to know what the colors "should" look like. I need to compare at the site where I can easily detect the subtle differences between the recorded picture and the original view. Maybe I could do it with cool/warm (80A,B,C..,81A,B,...) filters... Which ones would you recommend as a startup kit? |
March 2nd, 2004, 03:26 PM | #5 |
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Also be aware that in the conditions you mention
high noon, white snow, etc., that the actual daylight color maybe as high as 10,000K, NOT 5600K.
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March 2nd, 2004, 03:35 PM | #6 |
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I don't know if you tried this, but you mentioned white balancing using the snow. Try using a white card instead. Might avoid the problems with the snow having a bluish cast which warms the image.
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March 2nd, 2004, 03:42 PM | #7 |
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Ralf, these too warm yellows and the desaturated greens, are you evaluting those things on a calibrated monitor? Remember displays have "whitepointss" too, and can desaturate yr image if not callibrated well.
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March 2nd, 2004, 05:52 PM | #8 |
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Re: Can't get the colors right in ambient light...
<<<-- Originally posted by Ralf Strandell : It was a winter day at noon, overcast (and the sun behind the clouds was relatively low here at 65 degrees north), snowing, almost no shadow and lots of snow on the ground. ->>>
It is the special light: winter, low sun. I got the same problem with my Canon Photocam in the same situations. You see this problem in much newsshots on TV also. My only advice is to shoot earlier in the day. This light is very difficult to compensate for. I don't know how to correct this. Honestly I could not get it right as I wanted in photoshop. This light seems not to satisfy the temperature expectations. |
March 3rd, 2004, 03:12 AM | #9 |
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On the Sony TRV950 I have to keep the color saturation set two clicks below the default or similar color balance problems occur even with the manual white balance.
If you have a color saturation or color levels adjustment turn it down two clicks. This will likely solve the problem. Near neutrals, with amplified color saturation (as Sony does), are very difficult to maintain. Turning down the color saturation more closely matches the professional film "look" from a color perspective (Kodak NC especially). White balance is more robust with reduced color saturation as well. With the modern TV saturated phosphors offering more color saturation, and the Sony gain up on saturation.....well....we have plenty of saturated color....but the near neutrals are what is critical.
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