Tags: #<Tag:0x00007f3c682a9198> #<Tag:0x00007f3c682a9058> #<Tag:0x00007f3c682a8ef0> #<Tag:0x00007f3c682a8db0>

(Alexis) #1

Is there anyone making DCDM from Reslove?
Should I render a P3 RGB first?
been having some issues rendering my project directly from ACES to DCDM.
Can’t reverse the transform accurately.
Any suggestions on how this should be done. You can download a few frames from here: https://we.tl/utLlTRcRhd
Thank you guys.

(Dermot Shane) #2

that is what i do, then make the DCDM from an RCM timeline, with the input/timeline/output set to P3

seems to work acceptably well, i only make festival screeners, making a DCDM means it’s fast and easy to insert new mix’s, VFX Credits and burn a DCP in a few min, wel as fast as your disks can move the files, and maybe 5 min to create the XML

I send the same P3 files to a facility when a bonded/encrypted DCP is a delierable

(Borislav Konstantinov) #3

Yes, my workflow is ACES and DCDM for ODT. I try DCI-P3 but I found a differences in final DCP and in waveform. I don`t have any problems.

(Jim Houston) #4

They are completely different outputs.

The DCDM is X’Y’Z’ with a Illuminant E white point for XYZ. (coming from D60 white)
DCI-P3 with a DCI white point (.314,.351) is an RGB color space for direct mastering of a device set to that color space.

(Antonios Arapostathis) #5

Sorry, there is something I don’t get: I do my grade normally, then select DCDM as ODT. But then how should I render my TIFFs? Should I select TIFF XYZ 16bit in the render tab (probably causing a double transformation?) or must I select TIFF RGB 16bit (risking that some of the XYZ colors become out of gamut?) Please help.

(Sam Richards) #6

Hi Jim, Could you elaborate what the correct workflow is for outputting to XYZ for a DCP?

Where is the right place to look for documentation on this?


(Jim Houston) #7

Hi Sam,

Thanks for resurfacing this thread… which I see wasn’t completely answered.

For making a DCDM in Resolve 15, you should use aces_cc project settings. The Output Device Transform can be set to a g2.6 color space for grading, then switch the ODT to the DCDM (or DCDMP3clip). In the renderTab use TIFF RGB 16b not XYZ. The ODT version uses the proper scaling for the DCDM which the XYZ conversion in a render does not.

There is one caveat, the conversion in the DCDM ODT assumes the D60 ACES white point was used for timing. Equal value RGBs are assuming an output of D60. If a D65 was used for the adopted white, the conversion matrix from RGB to XYZ needs to be slightly different. I do not see how this is handled in Resolve and I assume it is not handled.

Validation of the output should check for gamma (2.6), gamut (reds are halved and orange), and scaling (the peak will NOT be 4096 in all three colors).

I think the different white conversions can be handled in the DCTLs that are in a different thread. But it is the same idea, don’t use the Resolve XYZ for the output conversion to a DCDM use a direct formula if possible, and just put the render tab in pass through of ‘RGB’

I haven’t searched for good documentation on this, but I think it may not exist.