If I recall properly, Kris recommended against that. The reason being is it's probably not a good idea to overlay two tone maps at once.
I think he meant UB820 HDR tone mapping vs SDR 2020. But you are definitely correct, you do not want to do SDR 2020 tone mapping.
I cannot think of any reason at all to recommend using HDR with optimizer from a UB820 with this projector or any other. The ONLY mode mode I recommend for projector use is SDR2020. This should provide the best HDR performance with this or any other projector vs their standard HDR implementation. I would also recommend this over any Arve curve as well, since that is a single or at best dual tone map solution that is trying to find a one size fits all solution for all HDR inputs. I would recommend using an Arve curve for sources like ATV4K though, or any other streaming input. But for disc playback, SDR2020 from MadVR, Radiance Pro or Panasonic UB820/9000 all day long over any other solutions for disc playback.
Kris, not sure if you've been following the madVR thread on the other forum or not, but madshi has created a tool that allows you to scan your UHD Blu-ray and create a file that will calculate the proper tone-map per scene ahead of time. The file creates data on a frame by frame basis to dynamically adjust the tone map for optimal results. Before this tool, as I'm sure you're aware, you could do something similar in real time but on the rare occasion you could see some luminance fluctuations within a scene, this tool supposedly fixes that issue. It does take about 15 to 20 minutes (depending on how fast your graphics card is) to render this file, but it's worth it to squeeze out that extra nth of performance this method offers.
Is there any movie in particular you'd like the file for? I've only done a couple movies thus far. Let me know what requests you have and I'll try and provide the file for you,It would be cool if something like this could be done for dynamic contrast systems too. When you think about it, most LCD based TVs and higher end projectors use some form of dynamic contrast. So the market is saturated with them. If there was some sort of standardized software that a dynamic contrast system could read, we could do the same thing here to avoid pumping and gamma shifts. The studios themselves could provide the file. I suppose it's too little too late on that one.
Kris, or anyone else I recently had my RS4500 calibrated and had an SDR2020 setting made calibrated through the UB820 to utilize it's tone mapping. the picture is phenomenal but I am noticing that is some low apl scenes that have a lot red in them the red at times looks like it's slightly blown out or I can see, for lack of a better description, noise in it. Any idea what could be causing it? If there is red in an outdoor scene w/ lots of ambient lighting it's not there only in dark scenes w/ lots of red tones in them. It's got me scratching my head?
How was the mode calibrated? Do you have a LUT box like a Radiance? What color profile in the projector is being used? (BT2020 or HDR). Can you tell me the titles you're seeing this and time stamps? I don't have a 4500 here but I have a Panasonic player and can test it with the same title/scene to see if it is player related.
What you're talking about is the reason that Dolby Vision (or to a lesser degree HDR10+) would be such a huge game changer for projection. Without even getting into dynamic tone mapping, the metadata would be able to tell the projector exactly what to do with a dynamic iris/laser on a scene by scene basis, eliminating pumping and weird gamma issues.As for files, any and all that you have are appreciated. Even if the data is simply a text file with the info about the movie. I've heard there is going to be an update soon that will compute the Fall numbers without taking the bars into account for scope films, that should be an improvement too. But for now, I just really need the display max (or 99.9% value for measured MaxCLL) and the avg and measured MaxFall data.
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