Film-Tech Forum ARCHIVE: Scenes become a bit pinkish after DCP conversion

This is topic Scenes become a bit pinkish after DCP conversion in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Rayjohn Tagayon (Member # 9659) on 08-08-2018, 11:15 PM:

I've been noticing lately that after DCP conversion some scenes from a film we color grade become pinkish. We do our grading on a rec 709 dcp projector, NEC model, davinci resolve on a mac pro. Video out is blackmagic ultrastudio 4k via HDMI.

Most scenes that have this issue are mostly during scenes where there are flashing white lights. Like for example, a shot in the night where there's a storm. On grading it's as intended, dark and bluish as the dop instructed. But on DCP the light suddenly looks a bit pink. Any idea what's causing this? We use fraunhofer easydcp resolve plugin for conversion. Thanks!

Posted by Marcel Birgelen (Member # 6801) on 08-09-2018, 01:47 AM:

Keep in mind that DCI uses the DCI-P3 color space and not Rec 709. Now, the DCI-P3 color space is larger than Rec. 709, so conversion usually is not a problem. But if your primary delivery medium is Digital Cinema, you should ideally color grade it for DCI-P3.

You say that your DCPs end up being "pinkish", but have you ever tried to play it back on actual DCI equipment in a cinema? And if so, is it also "pinkish" there? This to ensure that your own playback isn't flawed, while the DCP itself might be fine.

Also, as an alternative, have you tried using DCP-o-Matic to generate a DCP? DCP-o-Matic is a free tool which takes most common A/V formats as input and creates a DCP from it. It will also do color-space conversion.

Posted by Marlon Martins (Member # 8823) on 08-09-2018, 03:12 AM:

i had the same problem with some DCP i created using OpenDCP, and as mentioned, the cause was the wrong selection of colorspace. i set as "P3" as i knew it was the colorspace for DCP, but that setting was for the SOURCE colorspace, so the program could do the proper conversion TO P3.

changed to Rec.709 and sRGB for testing, and the color was ok.