vray to nuke

[andin]

hi all!

i was wondering if someone successfully exported vray .exr files from max to nuke....and got the same image as the render of course !
cause i have some issues with the gamma of the output files and also not sure if it s possible to export the motion pass ? and the proper way to composite it back for motion blur...and z depth...

so any nuke expert here ? willing to share a tree view ?

and maybe i m mistaken but i haven t seen a compositing post so far so maybe a new section for this or am i the only one interested ?

thanks !

[3Seventh]

Hope this helps a bit: http://fxguide.com/forums/showthread.php?p=27925

[andin]

thanks !

man

these links are nice will definitively help me but no info on motion pass use.

thanks for sharing!

[instinct]

Motion Pass works fine. Just add VRayVelocity element, untick clamp and tweak the max value to your scene scale/units. Can be used straight out of the box with Nuke's VectorBlur Node. See this thread too for example:
http://www.chaosgroup.com/forums/vbu...ectorblur+nuke

Regards,
Thorsten

[batu]

Thanks

Thanks for the info 3Seventh and Thorsten.

Where I work they block certain types of files.
So I dug a little bit and found the same video located else where.

http://www.vfxvault.com/vfxvault.com/Tutorials.html

Just in case anyone else has similar issues.

[andin]

an overbright comp ...help !!!

hmm something strange...

i followed the tutorial from hugo guerra step by step
i got all my passes in the exr and the final exr is ok i think as i checked the passes with the layercontactsheet node...

BUT when i comp it back in nuke i get an overbright image ...anyone a clue ?
cause appart from that everything seems ok... so i wonder if i have done something wrong when rendering... or if there s something not correct with the nuke settings...


please anyone a clue ? i feel like i m not so far from a correct workflow but that drives me crazy...

[instinct]

Did you render out linear or sRGB ? If the latter you have to switch your Reads to sRGB as EXR is by default interpreted as linear.
On another note did you use any colour mapping ? if so do you have "Apply color mapping" on in the Elements ?

Regards,
Thorsten

[andin]

finally working !!!

at last ! finally the comp is working!

as you mentioned i had to render in linear because even if you switch to srgb in the reader the exr is ok but it doesn t go well with the passes on the output so i re rendered everything in linear and now it s working ok

happy ! thanks again for the links !

[instinct]

The Problem there is that sRGB is nonlinear alltogether (it's not even proper gamma heh) so that introduces all kinds of issues...