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Color Shift with X3200 and FOB47
http://www.paulcbuff-techforum.com/viewtopic.php?f=8&t=22		 Page 1 of 1
Author:  MLYoung [ Fri Dec 11, 2009 6:19 pm ]
Post subject:  Color Shift with X3200 and FOB47
I completed a lengthy photo shoot about 2.5 – 3 hours is how long the light was on with modeling lamp the unit was on ½ power for the whole shoot. The first 175+ images were running about 4650K temp. according to lightroom 2 with good accurate color and skin tone. The last wardrobe change and 20 shoots all came in at 4000K temp with the expected blue cast at that temp. Nothing was changed for these last shoots as for as camera CB, the X3200 power setting, light modifier, exposure and distance from light to subject. Camera Nikon D3, Nikkor 85 f1.4, ISO 200. I will attempt to duplicate the results but I am stumped as to the shift. ANY Ideas?
BTW the last 20 were saved due to RAW capture and Lightroom 2 just batched the last 20 at 4650k.
Thanks,
MLYoung
Author:  Luap [ Fri Dec 11, 2009 10:35 pm ]
Post subject:  Re: Color Shift with X3200 and FOB47
Several questions with this scenario.

First a color shift from 4650 to 4000°K would produce a yellow cast, not blue.

Second, an X3200 at 1/2 power produces about 5450°K unless it has the old "color corrected" tubes, which might drop it to 5100°K. At a given power setting they simply don't vary in color temperature . . . 30° perhaps from very cold to very hot. For them to output 4650 at 1/2 power I would suspect a rather yellowed (smoke, etc) softbox, a non neutral shooting area or an inaccurate neutral grey test card (most are off by several hundred degrees from patch to patch, as are most cameras from one exposure level to another). (Color meters - even at $1300, are even worse from one exposure level to another).

Since the change occurred after a wardrobe change I would suspect a change of color in the shooting environment - different background color or even the color of the clothing.
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