• ARRI

  ALEXA – Transcoding

  Posted by Kim Fox on May 18, 2011 at 5:13 pm

  Hi all,

  Okay, I’m new to the ALEXA, and I need a little help.
  As I understand it, the camera records in either ProRes 4444, or ProRes 422. I’ve just gotten the dailies for a feature, and it looks like they used a mix of both?

  The editor would like everything in 422 (LT), and he said that everything needed to be transcoded.

  My questions, and I apologize if any of these are idiotic:
  The 422 that the ALEXA is recorded into is (HQ), correct? So even if a clip was recorded as a 422, it would still need to be transcoded to 422 (LT), right?
  How can I tell if a clip is 422 or 4444? (I’ve been looking at clips with “Get Info,” but that feels pretty cumbersome.)
  Is this something that has to be done one clip at a time through Compressor?

  Thank you, thank you, thank you to anyone who can help with this!

  Kim

  Bastiaan Houtkooper nsc replied 14 years, 12 months ago 3 Members · 2 Replies
• 2 Replies

• 

  Illya Laney

  May 18, 2011 at 9:13 pm

  If everything needs to be transcoded to LT, then you can just throw one compressor setting on everything. If I’m forced to use compressor, I’ll usually set it up by camera roll to stay organized and If you have 422 and 444, I’m thinking the 422 and 444 would be separated into different camera rolls anyway.

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• 

  Bastiaan Houtkooper nsc

  May 20, 2011 at 6:05 am

  Kim, the camera can record several different formats including 4444 and 422 (div flavors)
  Most people will use 4444 but this runs only standard speeds. If you need 50-60fps you have to go back to 422. THis switching can be done by take, no need for diff cards or project settings.

  You might also see LogC and REC709 recordings. Another reason to transcode if people shoot LogC. to get the right REC709 in edit.

  I am using Resolve to create offline files, ARRI has conversion LUTs for LogC -> REC709 on their website and a lot of information. https://www.arridigital.com
  I suggest you read through this before you touch the material…..

  Bastiaan

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