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[Piggly]

I have a multi camera rotomation scene set up for motion capture and while I have undistortion vector files for my main camera, none were provided for the witness cameras.
In order to get correct motion capture information from the witness cameras I have let syntheyes solve the distortion and have generated undistorted plates from syntheyes.

I am wondering if anyone can help me :

with generating a UV distortion and undistortion through syntheyes (of the calculated undistortion in the cameras) to use in a nuke setup.
(obviously I have the undistorted plates but a UV file would be good too. )

I dont think Syntheyes can process .exr files?
Also to note, the witness cameras have had no grids shot, the undistortion is calculated using geometry, with the witness cameras solved indirectly to the main camera.

Any comments much appreciated.

[borgus]

hey piggly!

good question... Syntheyes can definitely process exr sequences.
You could generate a uv map with the regular format of your sequence
im Nuke using two ramps. Then change the footage to your
new/undistorted uv map inside SE, run the lens workflow and export
the undistorted uv map with "save sequence" (as exr). Does that
work? I don't have Nuke where, but that's what I'd try....

Hope that helped..

-Seb

[Piggly]

Hi Seb,
Thanks for replying!
Yes in theory this should work,as much as the lens workflows 1&2 state, I guess my confusion lies in the cropping/padding part of things, that is, I have.calculated the lens distortion, used the lens workflow script 1, so my sequence becomes undistorted and slightly zoomed in, and from there I have rendered out frames. If I replace this sequence with the "ramped UV image" and redistort the black pixels wrap in around the edges, so this UV image needs to be overscanned to start with. From there I get a bit confused and am wondering if I should be working another way, perhaps with padded HD footage to start with. My poor brain!

[borgus]

Another way to get around these uv maps is to use the open source
syLens plugin for Nuke. I didn't check it personally, but I heart that
it works quite nicely.

It's a distort/undistort node for Nuke which uses the same algorithm
as Syntheyes to do it's work. It's probably all you want for your
Syntheyes to Nuke workflow.

https://github.com/julik/sylens

Best,

Sebastian

[Piggly]

Thanks, yes I did see that, I will check that out today.
Thanks for your help Seb!

[borgus]

Hi!
Did you also try to use the "Nuke distortion grid" export function? I'd like
to know how it works...

[Piggly]

Hey thanks for pointing this out! It actually looks pretty cool, and could be exactly what i want! thanks seb!

[borgus]

found it by accident