Wednesday, 22 December, 2010

Arri Alexa Avid workflow

I keep getting asked about the workflow for editing with Arri Alexa media. Here, people mostly refer to the Apple ProRes 4444 Quicktime movies that the Alexa shoots. In India, as far as I know, we don't (yet) have an Alexa equipped with a Arri RAW recorder, hence ProRes 4444 is, for the moment, Arri Alexa media.

Most people have queries about editing Alexa media on an Avid Media Composer. Particularly Media Composer v 5 which can 'soft import' files without creating Avid MXF or OMF media, just like how FCP imports media.
Older versions compulsorily import media so that's another story.

FCP can easily edit the native files. Or you can batch convert to ProRes LT or ProRes Proxy to save space. 

So, as I began putting down points, I turned to the 'net to check if anyone had reported issues in forums. There were some issues, but these will go away with more work with Alexa and as software improves. So no point taking them up at the present.

While reading up, I came across Oliver Peters very informative blog Digitalfilms. This outlines the process in detail with pictures.

Here is the link

You need to try out his procedure first hand on a Avid Media Composer v 5 system to understand the simplicity and elegance of its working. 

Also, if you're working on an Avid Media Composer on Windows, then maybe you need to get the Apple ProRes decoder for Windows.
That's in case your QT Player on Windows can't open Alexa files. If it can, then don't bother with the plug-in.

Peters also has an explanation for working with Arri Alexa files in FCP. And a link to Nick Shaw's plug-in to make a quick and rough log to lin conversion of Arri LogC Quicktimes. This conversion is for preview purposes only. 

Unfortunately, Apple Color does not do log to lin for QT, only for DPX, else that would have been a great workflow too. 
But if you fiddle with the curves in the Primary room (of Apple Color) as well as, try auto balance you can get a neat looking linear image. You can even get carried away and believe you can grade your media yourself. In that case, get yourself a Tangent Wave or Euphonix grading panel, and a good experienced colourist, and who knows, you can do DI at home.

More on Alexa adventures as I lay my hand on some stuff to do myself.


  1. Till now, is there any movies or Commercials finished on ARRI Alexa in India with Prores 4444.

    The reason being is the ARRI metadata cannot be changed on the post with the prores, wondering how DOP's manage their requirements...!!!

  2. There are several commercials and at least one full length feature shot on Alexa in India. The three equipment hirers who hire out Alexas here in Mumbai and one in Chennai have their cameras booked several times a week so a considerable amount of shooting is being done on Alexa in India.

    About changing Alexa metadata post shoot, you need to specify what you need to change. When shooting ProRes, you can grade the files as is on Smoke for Mac, or Resolve on Mac. Even on Quantel eQ.

    If you shoot ArriRAW, you can change ISO settings and colour balance after the shoot if that is a necessity. At least one equipment rental company has got, or is in the process of getting a Codex ArriRAW recorder.

    But the ArriRAW files consume huge amounts of disk space, like 15 GB per minute of shooting. So before shooting ArriRAW, one needs to make up a good data storage, backup, archiving and conversion workflow.

    Neil Sadwelkar

  3. hai,

    What will be the file size of pro res 422 & pre res 444 in one minute recording


  4. My post on the Aja KiPro

    carries details in ProRes data rates and file sizes.



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