Originally Posted by Kris Deering
DTM off is basically static, and with that last build the coding on static was actually wrong, which is why everyone keeps seeing so much disparity. That will be resolved shortly.
Looking at your settings, 400 is probably good, if not slightly low. I would look at some really high nit content to see if that is allowing enough latitude without artifacts. The Meg, the Spears and Munsil 4K disc and Starship Troopers are all good high nit discs to look at.
My biggest concern with your setup would be the LUT set to HDR. For your setup I would highly suggest SDRP3 with gamma output set to SDR. Then have the projector calibrated to P3/D65 with a gamma of 2.4. If I am understanding your setup, you are double tone mapping, which would not be advised.
Hi Kris; thanks, interesting that DTM off is currently weird. I had wondered as I'd never noticed such a big difference before from turning DTM off.
I was previous to the current version using a fair bit higher than 400 max light as it looked better (600 most often recently) - I tried Jim's recomendation of 2-4x and disliked it, but 400 seems OK. Currently 400/26 for low ratio seems to get me closest to the behaviour of SDR areas of HDR discs, but I'm going to keep playing. I dislike having max light as low as Jim suggests (only 3-4x peak nits) because it seems to give problems with highlight areas (ie faces in sunshine) which seem to lose all detail and surface contrast.
I'm only tone mapping in the Pro. The JVC X7900 is in profile off mode with gamma set to 2.4 (but not calibrated - as it is in profile off autocal has no effect). I've tricked the projector into slipping the filter in with profile off which you can't do from the menus, which gets me the completely linear colorimetry of the profile off mode with the native panel gamut and gamma (so the LUT is also correcting the gamma droop)
The profile off / filter on mode of the projector is profiled with Lightspace, and then a 2.4 power gamma P3 LUT is created (because it is closer to P3 than 2020, so need to waster RGB code values) and the Lumagen output is set to P3 with the LUT having 2.4 SDR gamma. Seems to work...
Edit: interesting, I see Jim just updated his recommendation on max light prior to me posting. I'd been using 600 (sometimes 700) for a few months and did think it looked very good, though I thought it seemed a little darker in some scenes with the most recent release.