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Canon 5D, Colorspace, Exports
I feel like I’m going crazy here. Let me explain.
I’ve shot some footage on the Canon 5D: 1080p 23.98. My method of working with the files is trascoding and working as AMA.
Part one in question:
I transcoded to Avid DNxHD 115 RGB.I was told the Canon 5D shoots in RGB colorspace, so that’s what I should transcode as, right? Additionally, my decision was made based on what it looks like in my calibrated monitor while in Avid. I have a Matrox MX02 mini calibrated using the Avid 1080 colorbars. I imported the clip into Avid (before deciding to do AMA) as both 709 and RGB, and the 709 was way too dark in the monitor.
The resulting transcoded DNxHD RGB files are very washed out.
SO now when I do a Same as Source QT ref export, it comes out washed out, like the transcoded files look like on my computer monitors (not the calibrated monitor) in Avid. (Which makes sense, since they’re just referencing the transcoded files) And an H.264 export at best quality looks close to the original, unaffected clip straight out of the camera.
Here’s a picture of what I mean:
https://www.kimberlyhuston.com/Files/Example.tiff(The picture is top left: unaffected camera clip. top right: H.264 export from the sequence. bottom: Same as Source QT reference export. By comparing the curtain, the bottom file is more washed out and blockier. Especially at full size.)
So I guess my first question is: Was I right to transcode the clips to RGB?
My second question is: Why do the clips look so washed out after transcoding and while playing them in Avid?
My third question is: Why does Avid export the files so much darker than it’s displaying?(I’ve had all of this happen before on a previous project, but I thought it was due to the files initially being processed through and exported from FCP before importing them into Avid. But I guess that’s not the case.)
I was reading about the whole Macs now displaying the correct gamma, and Final Cut compensating for it. Then when Snow Leopard came out, Macs with that OS now display the correct gamma… So I checked my gamma display on my monitors (outside of an NLE) and it does say they’re displaying at 2.2 gamma) So theoretically the gamma issue is no longer an issue, right? The difference between my computer monitors and my calibrated monitor is pretty drastic in contrast and brightness, even though I’ve used the monitor calibration tool from my video card on my computer monitors as well. So it’s not like they’re THAT far off.
Anyway, I’m having a hard time knowing what program to trust, what monitors to trust… what settings to trust.. And it just seems odd to let the footage be so degraded before working with it Avid, to then have to compress back to normal.
Anyone know what’s going on?
Avid Media Composer 5
Mac Pro 2 x 2.66 GHz Dual-core Intel Xeon
NVIDIA GeForce 7300 GT
Snow Leopard -
10 Replies
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Video is 16-235, computer screens display 0-255. So video black, on a computer screen, look greyer than full computer black.
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I’m tired tonight so just a wild guess…
Do you have perian (the QT codec) installed?
Best,
Jeff G
Apple Master Trainer
Avid Cert. Instructor DS/MC
Avid & Color Videos Vasst.com
Compressor Essentials Lynda.com -
Yes, I do have it installed.
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Apparently the Perian codec messes with the way AMA reads H264 files.
https://community.avid.com/forums/p/88965/505007.aspx
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Interesting. I transcoded OUTSIDE of Avid though. So I never AMA’d the H.264 files. So I’m not sure if it applies. Unless Perian is affecting the way ALL programs are reading and displaying H.264 and would therefore affect how all other programs are letting me transcode from H.264.
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I bet it affects any application using Quicktime.
Also: how did you do the transcode, and with what settings exactly?
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MPEG Streamclip.
Export as Quicktime.
Avid DNxHD Codec > RGB, 1080p 23.976 DNxHD 115 8-bit1920×1080 (unscaled)
unchecked interlaced scaling (though I guess that doesn’t matter)
uncompressed audio.
I’ll have to do a test of it with Perian uninstalled then.
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You have to be careful how and where you decide if something is looking washed out. Have you read this document?
https://www.xs4all.nl/~terburg/Publications/601_709_RGB.pdf -
Ahhh. Thanks! That clears it up.
It sounds like in summary, if you don’t want Avid to do anything to your colors, import at 601/709. Then color correct the blacks and whites back to legality, if you have any from the source file being RGB. And if you want Avid to clip the illegal blacks and whites for you, or if you file just IS RGB, like a screencap or graphics, load as RGB.
And if the file isn’t RGB, loading it as such will make it look washed out on computer monitors because you’ve just cut out the brights and darks of your footage’s latitude. But the reason 601/709 looks darker in blacks and brighter in whites on the calibrated monitor is because it still has illegal blacks and whites displaying.
Also it seems to still maybe have something to do with h264 because at work I’ve loaded quicktimes with the animation codec and at either 601/709 OR RGB it looks the same, I believe.
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Unlike most others, Canon cameras (5D, 7D) actually store video 0-255, resulting in crushed blacks/whites and messed up colors if not properly decoded.
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