Latest post Thu, Mar 28 2019 5:31 PM by QOTN. 9 replies.
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  • Sat, Jan 10 2015 11:30 AM

    • Euchrow
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    Arri Alexa 2K Anamorph Desqueeze inside Avid

    Hi there,

    I'll be editing an upcoming feature shortly. It will be shot on an Arri Alexa in 2K Anamorph (2048x1536, ProRes 4444). We'll be working in a 1080p24 HD project.

    Together with my assistant, I'm checking the workflow. We've got two options for the transcoding:

    - transcode to DNxHD36 MXF using Resolve. This has been tested and works. The idea would be to just do the resize in Resolve, and then apply a cube LUT inside Avid (source settings) to every clip

    - AMA the footage into Avid and then transcode to DNxHD36. The resize would then be done using the FrameFlex tools inside the source settings. This is where we run into problems. I can't find the right settings to desqueeze the Anamorph footage into 2.39:1 with the right proportions.

    I included a picture with the results. Source material is the Alexa Frame Leader which you can download here.

    Settings:

    - Resolve:

    • Import footage, set Clip Attributes -> Pixel Aspect Ratio -> Cinemascope
    • Create 1920x804 timeline.
    • Set Input scaling: Scale Full Frame with Crop.
    • Set Output Scaling: 1920x1080, Center Crop with no resizing
    Avid
    • AMA files into 1080p24 HD project
    • open Source Settings
    • Set Image Aspect Ratio to 2.39.1, Pillarbox/Letterbox
    As you can see, the Avid result isn't good. The circle isn't perfectly round, the image is too large and the luminance values are different. The Resolve workflow works, but I wonder what I'm doing wrong to achieve the same results inside Avid. Thanks for your suggestions,

     

     

     

    Alain

    Symphony 2019.6 on Mac Pro Westmere 3.33Ghz 6 core, 48Gb Ram, Nvidia GTX 980, High Sierra 10.13.6, BMD Ultra Monitor 2019.6 on MacBook Pro Retina 2018... [view my complete system specs]
  • Sat, Jan 10 2015 12:24 PM In reply to

    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Seems like AMA won't let you do that partial crop (the sides).

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sat, Jan 10 2015 1:13 PM In reply to

    • Euchrow
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Ok I found the solution in the meantime.

    FrameFlex Settings:

    Image size 2288x858

    Frame Aspect Ratio: 2.39:1, Pillarbox

    Remove 'full range to video levels' to correct the luminance levels.

    Transcoding in Resolve is twice as fast as in Avid though...

    Symphony 2019.6 on Mac Pro Westmere 3.33Ghz 6 core, 48Gb Ram, Nvidia GTX 980, High Sierra 10.13.6, BMD Ultra Monitor 2019.6 on MacBook Pro Retina 2018... [view my complete system specs]
  • Sat, Jan 10 2015 4:05 PM In reply to

    • jef
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Transcode in Resolve is fast, but you lose some metadata that you get by staying inside Avid.

    I would suggest you consider the full post path before making a decision.  How will the film be finished?  I would do a complete end to end test.

    Good luck,

    Jef

     

     

    Avid DS 11.0.2 R.I.P | MC "Well, it depends ..." mostly 8.11.0 but playing w 2018.12.6|OS 10.14.x - iMac 2017 - home system MacPro Dual 2.8 8core... [view my complete system specs]

    _____________________________________________

    Jef Huey

    Senior Editor

    Old Stuff  http://vimeo.com/album/3037796

  • Sat, Jan 10 2015 5:20 PM In reply to

    • Euchrow
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Confo and grading will be done on a Quantel Pablo Rio. Resolve was used on most movies I edited to transcode the rushes, it really works well.

    Another question, do you know if there's a big difference in IQ between the 'Sharper' filter and the 'Bilinear' resize filter? Bilinear is around 30-40% quicker on my machine. End result is a DNxHD36 mxf, so it will be quite compressed.

    Thanks

    Symphony 2019.6 on Mac Pro Westmere 3.33Ghz 6 core, 48Gb Ram, Nvidia GTX 980, High Sierra 10.13.6, BMD Ultra Monitor 2019.6 on MacBook Pro Retina 2018... [view my complete system specs]
  • Sat, Jan 10 2015 5:41 PM In reply to

    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    jef:
    you lose some metadata that you get by staying inside Avid
    What metadata would be lost? Dailies are done on third party systems all the time and one could argue get more metadata from the file than Avid QuickTime AMA plug-in. REEL ID from the embedded track is one example. An additional ALE merge is needed, but there is no less metadata in the process. FrameFlex metadata is better managed if you start and finish on Media Composer, but there are still many workflows where FrameFlex parameters are incorrect when going back back forth between Resolve which is more of a design/implementation at this point.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sat, Jan 10 2015 11:08 PM In reply to

    • jef
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Job ter Burg:

    jef:
    you lose some metadata that you get by staying inside Avid
    What metadata would be lost? Dailies are done on third party systems all the time and one could argue get more metadata from the file than Avid QuickTime AMA plug-in. REEL ID from the embedded track is one example. An additional ALE merge is needed, but there is no less metadata in the process. FrameFlex metadata is better managed if you start and finish on Media Composer, but there are still many workflows where FrameFlex parameters are incorrect when going back back forth between Resolve which is more of a design/implementation at this point.

    My thought was IF any finishing was going to be done in Avid.  But your point is solid. 

    My experience is that relinking material is easier when the path was AMA > Transcode (to lower quality) > Edit > relink to AMA and Transcode (to full quality).  I have only done one project where the original dailies were done in Resolve.  We got the relink to work, but it was a bit more fiddly.  That was several versions of Resolve ago.  Things must have improved from what you say.

    Jef

    Avid DS 11.0.2 R.I.P | MC "Well, it depends ..." mostly 8.11.0 but playing w 2018.12.6|OS 10.14.x - iMac 2017 - home system MacPro Dual 2.8 8core... [view my complete system specs]

    _____________________________________________

    Jef Huey

    Senior Editor

    Old Stuff  http://vimeo.com/album/3037796

  • Fri, Oct 21 2016 5:02 PM In reply to

    • malzane
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Hi Alain!

    I'm wondering if you ever found a answer to you issue with the Avid squeeze issue or did you end up using Resolve? I am in the same situation with a short film I'm working on (the footage is anamorphic shot in 4K UHD 16:9 prores XQ) and I can't find any answers. The footage I have also has a LUT baked in so I'm worried I'll lose the LUT if I transcode in Resolve. I haven't used Resolve so if you have a good workflow that you created for this would you mind sharing?

     

    Thanks!

    Malinda

  • Fri, Oct 21 2016 8:21 PM In reply to

    • Euchrow
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    • Joined on Sat, Apr 15 2006
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Hi Malinda,

    Well you can either transcode in Avid using the settings above or otherwise transcode in Resolve which is  IMHO the best option. You can find the required settings in my first post, or you can read the Alexa to Resolve whitepaper for more info

    Download (pdf, 1.31 MB)

    Symphony 2019.6 on Mac Pro Westmere 3.33Ghz 6 core, 48Gb Ram, Nvidia GTX 980, High Sierra 10.13.6, BMD Ultra Monitor 2019.6 on MacBook Pro Retina 2018... [view my complete system specs]
  • Thu, Mar 28 2019 5:31 PM In reply to

    • QOTN
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    Re: Arri Alexa 2K Anamorph Desqueeze inside Avid

    Would you happen to know where I can find those Alexa framing charts now? That link doesn't seem to work and I can't find them anywhere online.  I'm trying to use frame flex to de-squeeze my 2944 x 2160 picture to 2048x858.

     

    thank you!

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