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Author Topic: white point for dcinema. Pepo Razzari Film Handler Posts: 1 From: buenos aires, argentina Registered: May 2012 posted 06-04-2012 11:44 AM                     Hi people. We make dcps from time to time and test them at a showcase cinema. I would like to ask about two different problems in case anyone could help. I go from whatever source to xyz colorspace at 5900k and dcps look a bit on the warm side on screen. I have asked the thech supervisor at the cinema and he tells me the lamp (osram 4000 or 6000) is what determines the color temperature. I understand d65 is the widely used calibration but dont know how to check this on the projector and there is certainly a difference in color between 5600 and 6500 k. It is a Christie but dont know model/make. The other problem is that our dcps look in sync on a computer display but out by a frame on cinema. I have read somewhere the delay compensation in the audio chain differs from 3d to monoscopic. They are projecting 3d exclusively and my dcps are monoscopic. I told this to the supervisor but he tells me he does not have a way of changeing this. They use sony servers. Any instructions you could provide on how to figure out this information and possibly change settings? Thanks a lot in advance. Pepo  |  IP: Logged Robert Minichino Master Film Handler Posts: 350 From: Haskell, NJ, USA Registered: Dec 2005 posted 06-04-2012 12:26 PM                        The color data in the DCP file is in the CIE XYZ color space (scaled and gamma encoded). The reference white is at point [3794 3960 3890], which corresponds to the chromaticity coordinates x=.3140, y=.3510. The DCinema projector is calibrated by using a test pattern at [3794 3960 3890], and (essentially) setting gains on the imagers so that the resulting light on screen is [.3140, .3510]. The lamp's color temperature is corrected by this process. The actual white point setting happens during the RGB->XYZ conversion, which is on your side--if you set RGB white to D65, then it'll be D65 in the cinema. If you're doing the colorspace conversion correctly, it's possible that the cinema's calibration is seriously bad.  |  IP: Logged Yinghong Wu Film Handler Posts: 32 From: Suzhou Jiangsu China Registered: Apr 2012 posted 06-04-2012 09:12 PM                     We also make the dcps use with OpenDcp,And the color is good,Never met the thing which you met,Our server is Dolby DSS100 and projector is Christie cp 2000zx.  |  IP: Logged

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