I currently have Chromapure and am thinking about other solutions for LUT generation for my Lumagen 2021; Lightspace is the most obvious that comes to mind. I'd like to understand a little more about the workflow in Lightspace for Lumagen.

My understanding is that Lumagen has up to 21pt 1D LUT for greyscale in series with the 5x5x5/9x9x9/17x17x17 3D LUT. The Lumagen manual on these things is specific that the 1D LUT needs creating first to achieve the desired grayscale balance / gamma curve, and then the 3D LUT is generated with the 1D LUT in place and active.

Does Lightspace profile the display, generate the 1D LUT, upload it, and then profile again and generate the 3D LUT and upload that?

Or does it work another way?

Actually, Lumagen have the 1D and 3D LUTs the wrong way round in the Radiance...
The 1D should be in front of the 3D.
Lumagen actually had this correct originally, but a 'different' calibration company made them change it around to the incorrect setup they have at the moment...
This is something we are in discussion with them about.

But, we manage this through the way we handle the Lumagen within LightSpace, and we just null both LUTs, profile the display, and then mathematically calculate both the 1D and 3D, and upload at the same time.

This is the best approach for the incorrect configuration of the LUTs.

For a workflow see: http://www.lightillusion.com/lumagen_manual.html

Steve

Oh - and to discuss LightSpace CMS and Lumagen further I would suggest you talk to Gordon at Converget-AV, the UK reseller for Lumagen.
Gordon has used all the different calibration systems out there for Lumagen use, and now uses LightSpace exclusively, based on his testing of the final results, etc.

Steve

Thanks, much appreciated. Sounds "entertaining..." It did seem a little backwards to me, buy I don't know much about these things.

In your LUT guide (http://www.lightillusion.com/luts.html) you explain that 1D LUTS complement 3D LUTS mostly because of the difference in size, but it seems the 1D LUT in the Lumagen isn't that much larger than the 3D LUT (especially if you had a 17x17x17 3D LUT capable unit). Though I guess even at that kind of size, the expectation is that the 1D LUT effectively pulls the output in the right-direction so that the 3D LUT is (probably) doing less?

Yeah, correct.
There are professional LUT boxes that just use 17^3 LUTs, with no 1D.
But, you really need a 21^3, or better, 33^3 to not use a 1D LUT before the 3D LUT.

Steve