Colours coming out different/blacks crushed

[alor]

Thanks for all that. I'm now trying to make a dcp and getting an error which shows no search results online.

"Error: Could not start jeg200 encoding"

Anyone know why? It gets to a few % then does that.

[Carsten]

Is it a complicated composition in DCP-o-matic, or just a plain file? If the latter, just create a new project.

I would also suggest you first reset prefs to defaults under 'Tools', then increase the default encoding datarate in prefs to 200MBit/s. Then try again. With typical content, most automatic conversion settings work ok. Except in your case where you applied some cropping in your screenshot (perfectly okay).


Which version of DCP-o-matic are you using?


- Carsten

[mytbyte]

@alor: I am pretty confident that EasyDCP Player Demo (as I already suggested) will present your DCP correctly i.e. how it will be interpreted by a cinema DCI setup...also MPC-HC player with built-in LAV filters should give the same result as EasyDCP Player, except you probably will not be able to play it real-time...you should absolutely avoid Stereoscopic player or their JPEG2000 decoder for judging colors/gamma, use it only for sync and glitch test since it's pretty fast at decoding...

please note that this is a technical issue, not a color grading issue, it will only confirm that your input and output are identical or close enough on the same gear even if it's not calibrated, not a guarantee that it will look as expected artistically in the cinema...you really need to proof it in a cinema...

[Carsten]

Let me clarify that DCP-o-matic is not really doing something wrong here (although I called it 'a bug' above): Currently, the preview is always using the source color space in the preview window, so, changes in the color conversion dialog are not reflected in the preview.

DCP-o-matic always followed the approach that color conversion during DCP conversion is a formal, not a creative process, that's why there are no brightness/contrast/saturation dials in DCP-o-matic. So it's all about knowing your source color space/encoding - the target is always XYZ with a display gamma of 2.6. DCP-o-matic assumes standards to be followed.

That's why DCP-o-matic so far did not care about a realistic rendering of the converted color in preview. The moment you try to accomplish this, it can get complicated, because the software doesn't know your actual monitor parameters and wether it's calibrated or not. But it should if it pretends to give a proper color rendering. If you compare the same video file in different video players, you will always notice differences in their color rendering, even more so if they use different display techniques/hardware. Then add the effect of different video connections/monitors/settings/calibrations.

In general, DCP-o-matic does a proper job in converting colors with the standard profiles. You should only try to modify them if you are sure that your source footage has been created using non-standard parameters.

- Carsten

[alor]

Thanks everyone! Converting XYZ to RGB .709 colourspace in EasyDCP player does seem to put it back to looking identical to the original (though I was worried at first because everything looked cyan but I think that was some weird default setting the player had on). If only tutorials had explained this all to me! I would know I had been worrying about nothing.

Thanks everyone for all your help. It should look at least decent on the cinema screen now I expect. Also not sure if I had to but I converted the files from 25p to 24p in case there were issues with projecting in 25p.

As for the error... I was getting that on both projects with the new version of the program I downloaded yesterday. I reinstalled the older version and it seems to be working fine. The short one is already finished.

[Carsten]

The current test version (2.11.x) also comes with a player. Wether that player's image comes close to EasyDCP remains to be seen. Some DCP-Player Software even has a range of different playback XYZ-sRGB conversions to pick from. Having a choice usually is a good thing, but...

I guess Carl would have loved to look into your 'Error: Could not start jeg2000 encoding' error more closely, as he is about to release 2.12 as stable release, and any 'pending bugs' make him nervous. Which DCP-o-matic versions did you actually use, and is it in OS X (which version)?

- Carsten

[alor]

Hi Carsten, the version that made the error was the latest version listed on this site. I went back to the version I made a few months ago. I am on Windows 10.

[Googloiss]

...also MPC-HC player with built-in LAV filters should give the same result as EasyDCP Player

Hi mytbyte! I'm currently using the last version of MPC-HC (without install anything else, madvr, other lav filters, nothing, just the player, I only turned on color management and never touched other settings) to test my latest DCP (actually, only the mxf video file in it). From what I understood it's a reliable way to judge the conversion from the rec.709 source master file (a prores 4444 in my case, always viewed in MPC-HC), it should matches what theoretically I would see with a cinema projector?