Avid DS - offline files

[AaronPicot]

Those of you who edit/assist with Avid DS:

What type of offline transcodes do you most prefer to work with and why?

[Igor Ridanovic]

I am not sure if I exactly understand the question. I think you are asking what file types are preferred in DS in place of using the R3D files directly.

DPX files are the second best because of the optimal file size/dynamic ratio. However, using 3RD files in DS is not only better from the standpoint of color flexibility, but it is also faster than most third party transcoding solutions. Of course, I am comparing a DS vs. a single transcoding computer. It's a different story if you are using a solution that utilizes a render farm.

[AaronPicot]

Thanks for the reply Igor. Let me be more specific about my particular situation.

Got a Red feature coming up. Production has said they want me to do transcodes and it's up to post to tell me what they want. They haven't told me yet, and I just wanted to run some tests with my Rocket and see what media works the best and how long it takes, etc.
I don't know their exact specs, but I am thinking they have some pretty bad ass machines at this post house.
Is DNxHD a a good/bad option for offline on a DS? I haven't touched an Avid in ages, so I really have no idea.

[Chris Reynolds]

Avid DS is an online tool. Although it does have a timeline and a good one at that it is not a great tool for offline. Once you get too many event in the timeline it really bogs down. You are much better off editing with avid media composer.

Cheers, Chris

[AaronPicot]

Ah, I see. You know, maybe post is doing an offline on a Media Composer. All I heard is that they were editing on a DS. If this is just an online tool, then they probably have something else for the assistant.
Well, if it's a Media Composer, what is the preferred offline file?

[Peter Moretti]

Well the rule of thumb with Aivd use DNxHD. I don't see why it would be any different for what you are doing.

[MichaelP]

DNxHD 36 is a great offline HD codec if you know you are conforming at a higher rez in a product like DS.

Michael

[AaronPicot]

Ah! Now we're getting somewhere. I don't know much at all about DNxHD, so here's a few more questions.

1 - What's the difference between DNxHD 175, 117 and 36?

2 - When I export a DNxHD from RCX, it makes two .mxf files per clip. How come?

3 - what program can I use to view the mxf files quickly? Quicktime doesn't do it.

4 - If I wanted to transcode to DVDs for dailies, can I do it from the mxf files?

[MichaelP]

1. Those are the different data rates with more or less compression. 175 has the least amount of compression and comes in 10 bit or 8 bit. 36 has the most compression but is commonly used for offline as the picture quliaty is still high yet hold close to 20 hours of dailies on a 300GB drive.
2. MXF in Avid spits picture and audio tracks into their own files.
3. I use solutions from Calibrated Software to open MXF files in QuickTime: http://www.calibratedsoftware.com/
4. Most likely used the Calibrated QT decoder you "should" be able to get an MPEG encoder to read the files.

Michael

[AaronPicot]

1 - Very informative, thanks!

2 - I am getting 2 folders: MXF and AAF. the MXF folder has two mxf files in it (audio and video?), and the AAF folder has one AAF file in it (what's this?), and then I also get a "AvidExport.ale" file (which is what?).

3 - Looked into it.

4 - $180 just to view .mxf files in QT? I'm sure the software is cool, but it seems like I should be able to at least VIEW FOR FREE the DNxHD transcodes I just made in RCX. Is there another option, or did I miss the free plug-in for QT for something?

Wishing I knew more about Avid...

[MichaelP]

There is a demo version available here:
http://www.calibratedsoftware.com/downloads.asp

Subject to non commercial use.

MXF is the essence - the actual picture and sound files.

AAF is the pointer to that media that is metadata. Importing the AAF file is faster for the editor to import than it is to go find the media. So drag MXF files to Avid MediaFile folder structure (MXF/1) and then drag and drop all AAF files into the bin project. These will immediately relink to the mediafiles. There will be one AAF file for every clip and a clip can be 1 video and up to 24 audio.

The ALE file is pure metadata and contains the full set of metadata from REDCINE X, both timecodes, all color parameters whereas the AAF is basically tracks, 1 timecode and source file name as TAPE.

One can work with the AAF's alone or merge the additional ALE metadata into the clips.

Avid.com/red has an outdated RocketCine step by step guide that will take you through that on the Avid side which is basically the same steps as using REDCINE X.

Also sign up to the Avid+RED webinar on December 2nd that will go through all of this. See the main Avid section here for details.

Michael