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I installed the (free) LE version of Avid’s DNxHD onto bothWindows and Mac, in order to round-trip between Sony Vegas and FCP.  Having received no responses to my threads on forums for Sony Vegas and for FCP, I tried Avid’s forums.

• The “Avid on Windows” Forum:
  • PC MediaComposer to MAC FCP http://community.avid.com/forums/p/74442/416691.aspx#416691
    • Thread from August 2009.  Might well be out of date now.
    • If you export DVCProHD from your PC Avid you’ll want to check the “Use AvidDV Codec” box.  This will encode the file as AvidDV100 (which is Avid’s DVCProHD codec).  With the Avid codecs installed on your FCP system you’ll be able to read them.
    • Why don’t they mention DNxHD ?
• The “Avid on Mac” Forum:
  • Search on [fcp dnxhd]
    • http://community.avid.com/forums/p/84564/477328.aspx#477328
      • Error while loading DNxHD QT .mov into FCP
      • Someone with same issue as me: they rendered from Sony Vegas to DNxHD to import to FCP, and the media wasn’t recognized.
      • Thus far, that thread is inconclusive, with suspicions focussing on the precise format settings etc. and the fact that the media was rendered from Sony Vegas (as I guess the latter is relatively “unknown territory” to the Avid/DNxHD folks).
      • I copied this info (& thread link) to the Sony Vegas forum http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=720994&Replies=11.  Useful replies:
        • …a smalll but critical point; the codec DNxHD does all the encoding of the video stream, vegas does not touch the encoding process. At most, vegas may update the file headers and starting meta data as it closes the file. If Sony has an issue it will be there, but I would question FCP file handling when it opening the file.
      • ?

Problem:

• In Windows I export from Sony Vegas to AVI (CineForm).  In OS X I read the file into FCP and apply the SmoothCam effect, then export to ProRes.  In Windows, Sony Vegas, I replace the original file with the smoothed one.  The levels/gamma are wrong.

Solution (Search):

• Sony Vegas forum http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=718371
  • Use DNxHD
    •  Couple of tips re DNxHD:  709 color level assumes 16-235, and RGB assumes 0-255.
  • Force it back again: www.kenstone.net/fcp_homepage/gamma_mac_pc.html
    • But this presumably implies getting re-quantized twice (the roundtrip issue and the forcing), which for 8-bit footage I imagine could reduce the quality (banding).
• Uncertainties
  • Where and how does this gamma get applied?  In FCP I didn’t (knowingly) alter the levels (eg until it looked right), I just applied the SmoothCam filter.  So I guess it would look wrong on the (pre-SnowLeopard) Mac but I wouldn’t care.  Wouldn’t FCP then export back whatever it got but smoothed?  This one is really confusing.    Experiments needed (when I get time…) I guess.