Hi everyone,
I'm mastering a documentary today and want to output two versions, one with RGB colour space for playback on computer and on with 709 colour space to burn DVDs with
My Project is set up with the colour range between 16-235. So what I want to do is clip anything out side of that for both versions then export one clean with 709 colour space with the colours bound between 16-235 and one with the colours stretched to the RGB bounds 0-250
Does anyone have a good workflow for this? Is it right that I should use a video mixdown rather than an export?
And does anyone have any idea what the best formats would be to go to. I was thinking I'd do the RGB one to Prores HQ - so it's playable, and the 709 one to Mpeg2?
I'm open to suggestions.
Thanks,
James
Just export two versions, and label them accordingly.
I have "Avid SAS RGB" and "Avid SAS 709" presets that I use to export, depending on what I want. Might as well have the best quality mastering file available out of the Avid...then use an encoding program to make a file for your DVD.
-- Kevin
Thanks Kevin,
How did you set it up to clip to 16-235 (for the 709) and to expand to 0-250 (for the RGB)?
Cheers,
Avid always works in 709, so if you import correctly and color correct appropriately, you will be legal 709.
When you export, you can select 601/709 or RGB. I have one settings saved to each. 601/709 is a one-to-one ixel mapping of your sequence to 16-235, using RGB will remap to 0-255.
That sounds faaar to simple...
In your settings is it a Quicktime movie you're making? There doesn't seem to be an option to export as MXF except for the video mixdown which doesn't give an option for RGB
I've tried setting it to "Same as Source" but when I go to export it says "No valid resolution...". My clips are all DNxHD175 so I have no idea what it means by that.
I've tried exporting a quicktime and setting it to RGB. When I bring the clip back in to the project the waveform looks exactly the same, it hasn't been scaled to 0-250 (the image also looked degraded)
My format settings are as follows
Project type: 1080p/23.976
Aspect Ratio: 16:9
Color Space YCbCR 709
Raster Dimension: 1920x1080
Stereoscopic: off
I have exported an DNxHD175x video mixdown of the whole sequence for the grade on a DaVinci. And received a graded DNxHD175x video back with the levels within 16-235. I've reimported that to the project to lay titles over.
With Titles and a bit of grain the levels have dithered over the 235 line. So I want to clamp them. I'm sure I've been told that avid does that.
Am I doing something wrong?
Okay, so exporting to Quicktime is sort of working but is doing exactly the opposite of what I'm trying to do.
When I export as 601/709 it squeezes my already colour corrected to 601/709 video into an even smaller range. When I export as RGB it does nothing.
What I need to achieve is a 601/709 file that clips the 0-16 and 235-250 information and leaves me a clean unsqueezed 16-235 signal. And for the RGB to expand the 16-235 limits out to 0-250.
Surely there is some way to achieve this.
I'm thinking I could colour correct the whole sequence out to 0-250 and then export to the two different formats and that would work, but that's another level of colour correction and degradation of the image, and I'm working in a 601/709 project so why would I expand the levels out beyond the project settings?
I think you will want to read this document.
You mention reimporting into MC, so the import settings matter in the same way as the export settings do. RGB means remap (both during export and import) and 601/709 means "keep levels" (import and export).
Do not use Custom options in the Quicktime export settings (at least not when exporting to H264 and ProRes, as this causes gamma shifts), use Same As Source.
If SAS doesn't work, somewhere something somehow is not at an Avid native resolution. Find it or transcode or mixdown your sequence prior to export.
If you do need ProRes, transcode or mixdown to ProRes INSIDE MC, then export SAS. That gives you clean gamma.
Thanks! That looks like the perfect document for nutting this out with. I'm off to do some test with PDF in hand.
Okay, so I need to provide something that the client can play from their computer that will also act as a master.
I was thinking a Prores HQ would be the best for this as it's pretty universally playable, rather than an MXF as this is not. Am I right?
But in order to do that I need to transcode the sequence to ProRes HQ then I can export as Same-as-Source. That will then give me a Prores file with no gamma issues. Yes?
Thanks, I've only really got one chance to get this right. So if I'm wrong please let me know.
Thanks for the document, unfortunately, I've tested the RGB round trip to clip the 0-16 and 235-255 information and it hasn't worked. Somehow the levels that are outside the clipping areas are being retained so when I bring it back in importing 709 there is still dithered information outside the limits, when I bring it in RGB it has been stretched to the 0-255 limits.
So is there a better way of just clamping to the 16-235 values? I don't want to colour correct it, it's just white titles and some grain I've applied to the whole video that has lifted it, otherwise the image is perfectly color correct to 16-235. Is there a color safe limiter?
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