External matte on RED material issue (R14B5)

Hi.

I have an issue where i do external matte on another software like Mocha Pro.
When i bring it in it seems that Resolve assumes that my matte is different in size or aspect as it does not match up at all or it tries to scale matte up to match original red file i would assume on that case.
Logical would be to scale matte to timeline as we see all other image or have separate options for matte control?

For test sake i created UHD timeline (original red file is 7k), exported out UHD plate for matte making in another app, rendered test matte out, got is pack as matte in media pool and also as just image sequence.

So when i attach matte it does not line up at all. When i put on the top level video track the same files with screen as blend mode it worss perfect. So my rendered plate to VFX is UHD and my matte is also UHD. Not sure if this is just only scaling or is it timing as well.

I have had idea floating to get Fusion with OFX Mocha but now i'm not sure if that would work either in that case.

External matte control in Key tab should help it but does not work as one would imagine.
Offset dial gives seemingly random numbers and do not help as one would expect.

Any ideas on this?

I can send in some frames if needed.

HI Margus,

Can you share some frames? (With comments)

Hi.

Here:

https://www.dropbox.com/s/tnws3e5w6poi9 ... g.png?dl=0

Blue is from the external matte chained as matte and it is totally off.
Normal color is the same matte on second track with overlay or screen for testing.

External matte should line up like that but it does not.

So this is done on UHD timeline where the matte paint has input from the UHD resolution plate
but original cam file is 7k red. I wonder the timing or scale on track matte and just UHD from same matte file on video track to not match up at all.

I just did a simple test with a UHD project 3840x2160.
I have 2 source clips:
A UHD 3840x2160
Another clip 6720x3780 (fake 7K)

I created a timeline per source clip (TL = 3840x2160)

I created 2 mattes in Photoshop (a circle): one in HD, the other in UHD

Whatever the TL / source size clip and whatever the matte: Davinci Resolve positions the mattes exactly in the right position.

Davinci Resolve resizes proportionally to the resolution of the TL. It is on a static image while with Mocha, one is in dynamics. Maybe check the settings in MOCHA? I can not reproduce the issue.

I can upload frames separately, original in original size, matte frame and UHD framegrab.

If it's not too big: we can try