Hi!

I was wondering if anyone had any luck creating a lut in nuke that tonemaps values over 1 and displays it the same in mplay.

When i create an opencolor animlut from nuke it wont look the same in mplay.
Hightones gets clipped and not pushed down.
See the pictures. The one coming frome nuke preserves the hightones much better than the image using a lut in mplay.

If anyone have the correct setup for saving out luts from nuke that will make it look the same in nuke and mplay i would be very grateful!
Or is this a limitation using luts in mplay?

Thanks

Can you post your.lut file either just the header part or the full file? I'd make sure it conforms to the standards here http://www.sidefx.com/docs/hdk12.1/hdk_io_lut.html [sidefx.com]

Also, in addition to the LUT, does your nuke configuration apply any gamma correction to the image?

What command/tool are you using to generate the .lut file for Houdini?

For LUTs that deal with HDR images, you'll want the input range to be something other that 0…1, and you'll generally want to use a Log-based LUT. The output range can be 0…1 if you're flattening the HDR range to SDR, but otherwise it should probably match the input range.

The Log sampling gives you good precision in the 0…1 range (black-white) while giving fewer samples in the HDR range.

COPs allows you to create LUTs from a color correction chain, both linear and log sampled. The color correction COPs are tinted blue. Use the “Save LUT” menu item from the gear or node menu of a color correction COP.

Alternatively, the link vilhelmo provided describes how to construct HDR LUTs with log sampling.