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thefilmaddict
01-01-2018, 03:22 PM
I shot some s-log 3 footage with the Sony fs7. I believe it can capture around 14 stops of dynamic range. I was going to Output a video edited in hdr and put it on YouTube to test the footage on my hdr tv at home. Unfortunately, I donít have a hdr grading monitor. What nit level should I put my white level at? I will color correct relying n the scopes. I assume 1000 nits would be too much? I am using adobe Premiere for grading. Itís an experiment. I know this technology is new. I see other hdr videos on you tube. My home television does recognize these other videos as hdr and it looks pretty good. Just trying to duplicate the results.

Joshua_G
01-02-2018, 02:28 AM
I have no direct answer to your questions, however, at present, there is no standard, or set, max. NITS level for HDR monitors and TVs. See details in the following links:
https://www.youtube.com/watch?v=uCHDjlQKLXQ
https://www.youtube.com/watch?v=m2KLt3qgh50
https://www.youtube.com/watch?v=JdKwfEv145A

thefilmaddict
01-02-2018, 05:16 AM
Great links. Thanks! It looks like whites will be at 100 nits. Very helpful!

Joshua_G
01-03-2018, 03:06 AM
Watch again the videos in the links. I don't think they imply whites at 100 nits …

thefilmaddict
01-03-2018, 02:19 PM
I am pretty sure the guy from Sony said that white should hit 100 and certain highlights can go over. That being said, I've seen other tutorials where people go to 1000 (or higher) in resolve (which I do not own). I am having a tough time pushing lumetri (in premiere) to 1000 with my slog 3 footage. I can't find a Slog 3 to HDR LUT anywhere. That would possibly help.

AndreeOnline
01-03-2018, 02:43 PM
It'a important to separate "reflected white" from everything else that may appear "white on screen"—like a clipped highlight.

A central theme of HDR, regardless of flavour, is that reflected light (like a white wall, but not counting specular highlight off a chrome faucet) stays in the normal nit range, but that light sources (including the sky) can extent much higher. It's specular reflections, lights, sunlight and skies that can go up to 1000, 2000, 4000 or in theory 10000 nits.

thefilmaddict
01-03-2018, 04:23 PM
Youtube recognized my clip as HDR (so I exported it right in media encoder). I can definitely see more dynamic range, but the overall picture is dark on my HDR tv. I think that I need to move my whites to 1000 nits, but I can't figure out how to do that in adobe premiere. I am in a DNxHR RGB 444 UHD 59.94 Sequence. My scopes are HDR (I can see 10k nits -- 2020 Colorspace). Lumetri HDR is enabled. Any ideas? I haven't seen any adobe premiere tutorials on this subject matter. I have seen resolve tutorials, but don't have the paid version of that program. I also don't have a SLOG 3 to HDR LUT (not sure it exists). Thanks for experimenting with me.

cyvideo
01-03-2018, 06:04 PM
Alistair C. has some.

Camera SL3-SG3C-to-HLG-709 and SL3-SG3C-TO-HLG-2020 LUTs you can try out. There are also 22 Grading LUTs going from HLG-709 and HLG-2020 from native values to -3 stops. Haven't had a chance to try them out yet but once things settle down in the new year I'll try them out.... Hmm! Now where do I get an HDR 1000 Nit monitor from to view all this? Never seem to stop spending :)

You will find them here below Alistair's smiling face:

https://www.patreon.com/alister

All best to all for 2018!

Chris Young

thefilmaddict
01-03-2018, 06:53 PM
Thanks for providing the link to the Luts!!!

thefilmaddict
01-04-2018, 07:53 AM
I haven’t used the fs7 Lut yet. I must say, on closer examination, the original test hdr Files look pretty impressive on my hdr tv. The files appear dark on a regular tv. I think that’s happening because YouTube somehow changes the file to sdr on a sdr tv???

Biggest issue with hdr file is blockiness in the sky gradient. I thought 10bit would fix that. Perhaps the file is too compressed and I need to crank up the file size?

thefilmaddict
01-05-2018, 08:27 AM
I downloaded the sony luts. I am thinking that lumetri in adobe premiere is limited in HDR mode. I can't seem to get my slog 3 video much past 100 nits. When I add the SL3 to HLG 2020 Sony luts, nothing happens in premiere while lumetri is in HDR mode. I do have the free version of resolve and these same luts do seem to work. Perhaps Premiere isn't totally ready for HDR?

thefilmaddict
01-05-2018, 08:30 AM
I di d find this: https://forums.adobe.com/thread/2291318