I have some footage I am trying to transcode from Apple Pro Res to DNxHD.  However, the resulting QT is significantly brighter than the original ProRes QT, and loses all of its contrast.

I have tried toggling the settings, including changing 601 to RGB, "millions of colors" to "millions of colors+", etc. But I end up with the same result.

I will probably end up shooting the ProRes stuff off to HDCAM from FCP and batch capturing back into Avid, but it'd be nice to stay tapeless.

Anyone have any success transcoding ProRes and keeping the color correct?

Also, occasionally when exporting said QTs from QTPro 7.5, I end up with a black screen QT. This problem is intermittent. Sometimes it exports successfully, usually it doesn't (even with settings that have worked previously, and even if I trash the prefs). Anyone have problems with that?

When you say "I am trying to transcode from Apple Pro Res to DNxHD.  However, the resulting QT is significantly brighter", what are you using to convert the Pro Res QT to a DNxHD quicktime and why would you not just import the Pro res QT into your Avid at a DNxHD resolution?

Avid on a Mac actually has some issues with QT importing and exporting.  You might take the suggestion to master out of FCP directly to DNX before importing into Avid.  But that might not work, either.

I believe there's a chance you will be unable to find a setting that reproduces properly levels and color space.  The only way to get material from FCP into Avid correctly is to master back to tape, as you anticipate, and come to Avid through HD-SDI or firewire capture.

Don't underestimate what I'm suggesting.  Avid MC 3.01 is not compatible with Quicktime movies on a Mac.  You can't export camera video out of Avid to QT with proper levels...and you can't expect to reimport that QT to Avid for re-editing.  In every case the black level will rise.  And, depending on your setting, white levels will be lowered...or, worse, be hard-clipped above 235.

If you determine otherwise, I'd love to learn the details!

BLKDOG:

what are you using to convert the Pro Res QT to a DNxHD quicktime and why would you not just import the Pro res QT into your Avid at a DNxHD resolution?

I tried both QT Pro and Compressor (compressor actually fixes the "black screen" issue). I can't just import the Pro Res QT into avid, because I don't have (nor want) FCP and Avid on the same computer. Pro Res requires FCP v6 to be read.

er3456:

Pro Res requires FCP v6 to be read.

No it doesn't, it only requires the codecs. If you have FCP, even on another system, just drop the codecs into your Library>Quicktime folder.

Rusty, I don't know where you are getting your information but you are dead wrong. Avid on Mac is perfectly fine with QT. I have several systems running 3.x with no problems exchanging QT's with my Graphics department.

Apologies...I've discovered that the levels issue is with native XDCam footage.  What I describe is indeed true with that format.  However, the symptoms described are very similar to mine, so the problem may be similar.  Avid codecs do not expect another application to mess with 709/RGB levels.  XDCam is RGB and Avid handles these native files in an exclusive fashion.  As you might anticipate, DNx codecs are not designed to compensate and problems are introduced when exporting.

Perhaps the FCP files are not conforming to RGB or 709 level standards and DNx codecs either over- or under-apply levels compensation, depending on the setting.

er3456:

 

I tried both QT Pro and Compressor (compressor actually fixes the "black screen" issue). I can't just import the Pro Res QT into avid, because I don't have (nor want) FCP and Avid on the same computer. Pro Res requires FCP v6 to be read.

You can install the ProRes decoder on a system without FCP:

http://support.apple.com/downloads/Apple_ProRes_QuickTime_Decoder_1_0_for_Mac

I believe its technically against the EULA to install the full ProRes codecs without FCP.

Make sure you have the latest version of the Avid codecs. They can be downloaded here:

http://www.avid.com/red/AvidCodecsLE_DMG_1.10.zip

I suggest using MPEG Streamclip to convert the files: http://www.squared5.com/

BLKDOG and Friends . . . .

I want to turn Red files into DnX 145 or DnX 220.  I can't process the Red files directly to DnX MXF--for various reasons.  I want to make QTs and import them first into an Avid SD project--then Batch Import them to HD Avid Project for the conform (underpowered machine in Thailand).

For the QT masters: I could transcode to 1080x1920: ProRes HQ 10-bit, PhotoJPG, or Uncompressed 10-bit, or what do you suggest?

ProRes would be great--but I have had some problems with with the black levels as described in this post.  The system I'll be working on for this upcoming Red job is unknown/overseas.  UC is a bit heavy for this project--I'd rather lighten up a bit--but not out of the questions. What about Photo JPG?

Never done a Red job before that wasn't laid off to SR first.  Final delivery is SD PAL Letterbox for broadcast, but the DOP and I want HD for our own reels.

Best Wishes,

Paul B