FORUMS: list search recent posts

Alpha channel from Premiere to Final Cut doesnt work

COW Forums : Adobe Premiere Pro

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Allard DePallerd
Alpha channel from Premiere to Final Cut doesnt work
on Dec 1, 2017 at 3:27:28 pm

Hi guys, im trying to send a client of mine some greenscreen footage that I have keyed.
im using the latest Premiere on my Windows, and the key looks perfect en crispy.

I have exported within premiere, using the "Cineform RGB 12 bit with alpha at max bit depth" preset.
I changed the quality from 4 to 5, and I have checked " render at max depth" and "use max render quality"

To check the export, I import it in premiere and I put a red matte beneath it. Everything is fine and the transparancy is working fine.

But, when I send the file to my client..he emails me that the footage looks like crap, and that the key is all messed up. He's on the latest Final Cut pro.. it looks like this:



So my question is.. what am I doing wrong? Im not set on using that codec.. So any (lossy) codec that would work on his system with an alpha channel, is fine.
I already tried quicktime animation with million plus..but same story there.. didnt work.

thanks!


Return to posts index

greg janza
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 1, 2017 at 4:07:22 pm

If you're doing the keying on your end and sending your client a finished composited clip then there's no need to export with alpha channel.

And if it looks perfect in your system, export in any format that's convenient for the client.

I Hate Television. I Hate It As Much As Peanuts. But I Can’t Stop Eating Peanuts.
- Orson Welles


Return to posts index

Allard DePallerd
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 1, 2017 at 4:28:54 pm

Sorry, i must have explained it the wrong way...
I am keying it for this client..and then I send it to him so he can finish the compositing and the final video.
So im doing just the keying for him.. and he finishes the movie


Return to posts index


greg janza
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 1, 2017 at 4:32:05 pm

splitting the compositing up between two systems is definitely not an ideal workflow.

I'd recommend that only one of you do the actual compositing. That will allow for the best quality control. If the client wants to do it then just send the green screen shots straight.

I Hate Television. I Hate It As Much As Peanuts. But I Can’t Stop Eating Peanuts.
- Orson Welles


Return to posts index

Allard DePallerd
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 2, 2017 at 2:28:22 pm

yeah that's what I thought.. but I am afraid I can't convince him to do this. He want me to key it..but not to do the rest of the video.

So im afraid im still stuck with my initial question..


Return to posts index

Jeffrey Di Lullo
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 3, 2017 at 12:56:04 am
Last Edited By Jeffrey Di Lullo on Dec 3, 2017 at 1:28:20 am

If the alpha isn't looking correct I'd ask 2 questions:

1) how is he interpreting the alpha: premultiplied or un-premultiplied. Then make sure that it matches what you are outputting.

2) Can his system correctly read the Cineform codec. Have you tried sending the clip as ProRes 4444?
Larry Jordan recently wrote an article about Cineform and FCPX (Not sure how helpful it is in your situation as it doesn't directly relate to keying). https://larryjordan.com/articles/problems-with-final-cut-pro-x-and-gopro-ci...

What would it look like if you just sent over a black and white alpha matte of the keyed clip and the original clip (two clips) and have him use that to key in FCPX. You can render the alpha matte pass as PhotoJpeg or a PNG sequence or whatever you like. Considering that he wants to finish the composite in FCPX this would actually give him better control over the final composite and would be my preferred method.

Jeffrey Di Lullo
jeffedits.com


Return to posts index


Allard DePallerd
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 3, 2017 at 2:37:04 pm

Thank you for your reply,

You say " how is he interpreting the alpha: premultiplied or un-premultiplied. Then make sure that it matches what you are outputting. "
How can he see (and change) how he's interpreting the alpha?

That last solution sounds good.. So basically im sending him the alpha matte, which he will use to key right?
But can you tell me how I would export this? I have my footage, with the ultrakey effect on it to make it transparent. How would I turn this into a black white alpha matte that I can export?

thanks in advance.. your help is apprectiated!


Return to posts index

Jeffrey Di Lullo
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 4, 2017 at 2:26:50 am

Go to about 4min in this video to see how FCPX is handling/interpreting the alpha you are giving him.
https://www.provideocoalition.com/fcp-x-and-alpha-channels/
Have him toggle the alpha handling setting to see if that fixes the alpha for you. If it does great!

To export b/w alpha matte pass:
Go into UltraKey and change "output" to "Alpha Channel". This will give you a black and white alpha matte pass. Export the clip.

Jeffrey Di Lullo
jeffedits.com


Return to posts index

Allard DePallerd
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 4, 2017 at 8:33:02 am
Last Edited By Allard DePallerd on Dec 4, 2017 at 9:04:37 am

Thank you so much Jeffrey, Ill look into it right away. Does it matter how I export the matte? Is a H264 MP4 fine ?

Ill let you know how it went, thanks again


Return to posts index


Jeff Pulera
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 5, 2017 at 4:27:55 pm

While sending a matte will work, it's double the effort for you and the editor, with double the files and editor needing to set up the matte key composite for every clip.

I'm assuming you are on a PC, otherwise you would just export as ProRes for him.

Try this - download the Avid DNxHD codecs from Avid, which will allow you to create QuickTime .mov files with ALPHA that certainly ought to work in FCP. Editor may need to also install same codecs on his Mac. They are free.

http://avid.force.com/pkb/articles/en_US/Download/en423319

Thanks

Jeff Pulera
Safe Harbor Computers


Return to posts index

Allard DePallerd
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 6, 2017 at 1:46:19 pm

Thank you Jeff for your reply, i have downloaded and installed the codecs..
In the PP export window, i choose the DNxHR/DNxHD MXF OP1a format but then, i can choose from many different presets..
Im an not sure which one i need to choose, and how to enable the alpha in this preset

The source material is from a Canon 5D mark III (25fps, progressive)

SO can you help me out with the preset and setting i need to choose from this list?



thank you in advance!


Return to posts index

Jeff Pulera
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 6, 2017 at 7:27:09 pm

Well, this is a bit embarrassing, and I do apologize... but apparently Avid DNxHD does NOT support an embedded alpha channel! Not that I can see anyway, and I also Googled it and that appears to be the case.

Besides that little issue, the idea was that since FCP is so old, I didn't know if it would support the .mxf flavor of DNxHD which is included in Premiere export settings, so I had you download the QuickTime codecs which would give you a more standard .mov file to share with the editor.

So at top of exporter under FORMAT (1), you'd choose QUICKTIME, then go down to VIDEO tab, and under VIDEO CODEC (2) select DNxHD, then under RESOLUTION (3) choose a quality level. Based on your source, 8-bit would likely be suitable rather than 10-bit.

Perhaps go back to the other plan of providing editor with source video clip, along with the Matte version, but use this codec for the matte? See (4) and there is an option to Render Alpha Channel Only. When you check that box, it changes the keyed image to a black and white matte for export.



Sorry for the error - who builds a really great codec, then doesn't offer alpha channel support??!

Thanks

Jeff Pulera
Safe Harbor Computers


Return to posts index


Jeff Pulera
Re: Alpha channel from Premiere to Final Cut doesnt work
on Dec 6, 2017 at 7:36:20 pm

PS - in my screen shot example I'd selected a 10-bit "resolution" but given that your source video is 8-bit, then 8-bit is likely a better choice to make smaller files. Definitely 8-bit for the Alpha Channel export since that is just black and white and would not benefit from 10-bit color fidelity!

Thanks

Jeff Pulera
Safe Harbor Computers


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2018 CreativeCOW.net All Rights Reserved
[TOP]