The custom default RGB-to-XYZ color space conversion in Xport makes my ProRes video a bit brighter (and a bit clipped) when converted to DCP because the ProRes source has a different gamma value from that expected in a pure RGB Rec 709 source.
For ProRes source with the Gamma of 1.8, try a CUSTOM color space conversion using one of the sample LUTs with the 1.8 Gamma available in the LUT folder within the Xport installer dmg.
Alternatively you may also tweak the gamma in Compressor's Gamma Correction filter, values between 0.7 and 0.85 gamma correction in Compressor's video filter tab and continue with the default color-space conversion option in Xport.
Conversion: YUV to XYZ
I have a HD source with a YUV Color Space. Does QubeMaster Xport do an automatic conversion from YUV to XYZ or do I need to do that prior to giving QubeMaster Xport the file?
Yes, Xport does indeed perform the color-space conversion. However, the default conversion expects the source to have the full Gamut RGB values (0 to 1024), not the compressed gamut YUV values (64 to 940).
Re: Color Space conversion LUT's
DCI_XYZ_ITU-R_709_HD.3dl
The ITU-R 709 LUT is for HD video source material where the range of values used is 16-235 for 8-bit and 64-940 for 10-bit signals with a gamma transfer function as defined by the specification.
DCI_XYZ_sRGB.3dl
The sRGB LUT is for computer generated or processed source material in the Rec. 709 color space where the full range of values is used with a gamma of 2.2.
DCI_XYZ_NTSC_601.3dl
The NTSC 601 LUT is for older NTSC video source material where the range of values used is 16-235 for 8-bit and 64-940 for 10-bit signals with a gamma transfer function as defined by the specification.
DCI_XYZ_NTSC_SMPTE.3dl
The NTSC SMPTE LUT is for more recent NTSC video source material where the range of values used is 16-235 for 8-bit and 64-940 for 10-bit signals with a gamma transfer function as defined by the specification.
DCI_XYZ_PAL_EBU.3dl
The PAL EBU LUT is for PAL video source material where the range of values used is 16-235 for 8-bit and 64-940 for 10-bit signals with a gamma transfer function as defined by the specification.
DCI_XYZ_p3.3dl
The P3 LUT is for source material in the DCI RGB P3 color space where the full range of values is used with a gamma of 2.6.
DCI_XYZ_Kodak_2383.3dl
The Kodak 2383 LUT is for 10-bit log source material suitable for film out where Kodak 2383 Vision film stock emulation is applied to match the characteristics of typical print film.