Testings report

[tho_mas]

Oh, I forgot to mentionned, I exported in 709, not rgb from Avid.

me too :-)

[fredjeang]

Arrrrrrrggggg.....

Now, I've just take the same and exported with the same settings but this time in RGB and yes...now I have the gamma shift (strong one) and colors uncorrect

[tho_mas]

Arrrrrrrggggg.....

Now, I've just take the same and exported with the same settings but this time in RGB and yes...now I have the gamma shift (strong one) and colors uncorrect

the setting 601/709 means: no remapping applied.
The setting "RGB" means: remapping applied (luminance stretch to full RGB 0-255).
The same on import: 601/709 = no remapping. RGB = remapping (on import it's luminance compression instead of luminance stretch).

Back to your comparision. Just noticed you are on a Windows Computer... maybe Quicktime behaves completey different on PC (as sRGB is the system's color space). I think that explains the different outcome of our tests.

[fredjeang]

the setting 601/709 means: no remapping applied.
The setting "RGB" means: remapping applied (luminance stretch to full RGB 0-255).
The same on import: 601/709 = no remapping. RGB = remapping (on import it's luminance compression instead of luminance stretch).

Back to your comparision. Just noticed you are on a Windows Computer... maybe Quicktime behaves completey different on PC (as sRGB is the system's color space). I think that explains the different outcome of our tests.

Correct, the RGB shift was expected for the reasons you mentionned. What is crazy is that we are doing exactly the same settings, with the same monitor gamma but from 2 different OS and there is a difference. Apple in your case shows the shift (I assume you are on Mac) while in my case (PC) it displays correctly, both in QT.
The sRGB does not convinced me that it could give such a difference. Actually, when the shift occurs I loose almost 3 stops. It affects the luminance, everything. That is more than that IMO.

So working between the 2 OS is a mess.

[tho_mas]

So working between the 2 OS is a mess.

true.
Then again... als long as you stay within Avid and with Avid Codecs consistency is guaranteed. For export you can transcode to a higher compressed 8bit DNxHD codec and export "same as source". If you have to give the files to someone else just include the codecs ( http://avid.custkb.com/avid/app/selfservice/search.jsp?DocId=263545 ).
For export of small files, i.e. H264 you can use the x264 codec: http://en.wikipedia.org/wiki/X264
Export from Avid into x264 produces consistent results (see attachment). Just make sure that the settings in the preferences of x264 are correct (see attachment: do not assign a color space and leave "add gamma" unchecked).

[fredjeang]

Thanks for those usefull precisions tho-mas.

Cheers.