AVS Discussions
Projectors => Premium Projectors => Topic started by: Kris Deering on January 07, 2017, 03:17:16 PM
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Hey Everyone. Just thought I'd chime in with some thoughts and experiments I've been running the last few days. As all are more than aware of here HDR on projection is sort of a work in progress right now. I haven't had the chance to play with HDR with the newer Sony offerings since they've revamped with firmware, so most of these comments are based on my time with the JVC X750. Initially most were using JVC's recommended settings and then going from there using a fleeting amount of test patterns that are available to dial in a picture that looks good. The problem there is while it may look good, it is still a best guess approach at this point derived mainly from trial and error with other's settings or successes. The next step was converting the HDR output to a SDR output but retaining the WCG capacity of the video signal. This seems to work best with the Panasonic player at the moment, but even after many weeks of trial and error I still see issues with gamma, mild clipping and more with this solution. Since the WCG portion of the movie is mastered in relation to the HDR EOTF, I imagine we are still seeing an improper conversion down to SDR levels as you would have to take into account the change in color volume from the intended display luminance. Sure it can look good still, but I would almost argue that the same look could be obtained with standard Blu-ray by just using a wider color preset on the projector. Call me a video snob but I prefer accurate to intent images rather than images that just look good.
So I decided to try something that no one ever seems to consider or try, telling the player NO for HDR and having it map down to standard gamma and REC709 color. This still preserves the resolution bump offered by UHD and the 10-bit video. But the UHD standard was also delivered with actual specifications on how to do this conversion, unlike converting to SDR with 2020. Using this method I get a proper conversion for both gamma and color to SDR, and can view the movie with a proper calibration. I have to say, so far I'm far more impressed with this as the image never has that "it looks great, but there are a few things that still look off". Like everyone else I am hoping that solutions will come that deliver an ACCURATE fold down to SDR with 2020 color, but it appears we are not there yet. I am also anxious to see what can be achieved with a Radiance Pro that tone maps HDR down to the projector's true output in what appears to be a much more intelligent fashion. Until then, I think I'm going to stick with this (other than continuing experimentation with the other options for testing purposes) for now and just sit back and enjoy.
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Hi Kris,
Are you doing this on the Oppo 203? With the 203, I tried turning off HDR and using Rec 709 on a UHD BD, but it still looked a bit too dark compared to the BD counterpart.
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Kris,
For projectors sake, how many nits will we need to benefit from HDR? Do we actually need 1000nits? Some setups can get up to 300 nits but apparently, that's not enough.
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I was going to ask the same. I wonder if Brightness +8 on the 203 with HDR OFF would brighten the image properly and be more accurate than HDR Strip.
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I'm using HDR off with the latest public beta FW for the Oppo 203 with no issues in darkness. Have looked at several Blu-rays. Using the exact same calibration I use for standard Blu-ray (709 with BT1886 gamma). Colors look slightly more saturated than the Blu-ray versions do, but only slightly. Noticed this mostly with Revenant and Sicario so far (Sicario doesn't have the washed out appearance that the Blu-ray does in the opening sequence).
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Thanks, very helpful. Its nice to have people that can't use HDR or dont want to currently, to be able to have alternatives.
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Hey Everyone. Just thought I'd chime in with some thoughts and experiments I've been running the last few days. As all are more than aware of here HDR on projection is sort of a work in progress right now. I haven't had the chance to play with HDR with the newer Sony offerings since they've revamped with firmware, so most of these comments are based on my time with the JVC X750. Initially most were using JVC's recommended settings and then going from there using a fleeting amount of test patterns that are available to dial in a picture that looks good. The problem there is while it may look good, it is still a best guess approach at this point derived mainly from trial and error with other's settings or successes. The next step was converting the HDR output to a SDR output but retaining the WCG capacity of the video signal. This seems to work best with the Panasonic player at the moment, but even after many weeks of trial and error I still see issues with gamma, mild clipping and more with this solution. Since the WCG portion of the movie is mastered in relation to the HDR EOTF, I imagine we are still seeing an improper conversion down to SDR levels as you would have to take into account the change in color volume from the intended display luminance. Sure it can look good still, but I would almost argue that the same look could be obtained with standard Blu-ray by just using a wider color preset on the projector. Call me a video snob but I prefer accurate to intent images rather than images that just look good.
So I decided to try something that no one ever seems to consider or try, telling the player NO for HDR and having it map down to standard gamma and REC709 color. This still preserves the resolution bump offered by UHD and the 10-bit video. But the UHD standard was also delivered with actual specifications on how to do this conversion, unlike converting to SDR with 2020. Using this method I get a proper conversion for both gamma and color to SDR, and can view the movie with a proper calibration. I have to say, so far I'm far more impressed with this as the image never has that "it looks great, but there are a few things that still look off". Like everyone else I am hoping that solutions will come that deliver an ACCURATE fold down to SDR with 2020 color, but it appears we are not there yet. I am also anxious to see what can be achieved with a Radiance Pro that tone maps HDR down to the projector's true output in what appears to be a much more intelligent fashion. Until then, I think I'm going to stick with this (other than continuing experimentation with the other options for testing purposes) for now and just sit back and enjoy.
I'm getting good results using HDR - SDR BT.2020, but when I get some time I just might try this and see.
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Ive been happy too with SDR 2020, but have not done side by side. I guess Kris has and I get his point, where we have had the ignorance is bliss man this looks good take, once you compare to what it should be it brings up some good points.
The first movie I watched SDR 2020 was TMNT 2, after several unhappy attempts at watching movies with HDR. I was blown away at the detail, and the blacks, I never looked back.
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I assume that once DV is included in BR, and we get players that can send that information to the projector that we will be facing the same issues, in a DV capable projector, say maybe 2017 sony's??
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So I decided to try something that no one ever seems to consider or try, telling the player NO for HDR and having it map down to standard gamma and REC709 color. This still preserves the resolution bump offered by UHD and the 10-bit video.
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I wasn't aware you would still get 10 bit video. Good to know.
Thanks.
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I assume that once DV is included in BR, and we get players that can send that information to the projector that we will be facing the same issues, in a DV capable projector, say maybe 2017 sony's??
Doubtful we will have projectors that can do DV HDR anytime soon. 2020 maybe ?
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Ive been happy too with SDR 2020, but have not done side by side. I guess Kris has and I get his point, where we have had the ignorance is bliss man this looks good take, once you compare to what it should be it brings up some good points.
The first movie I watched SDR 2020 was TMNT 2, after several unhappy attempts at watching movies with HDR. I was blown away at the detail, and the blacks, I never looked back.
I have done side by side ( more like one, then the other, then back again ) between first 4K BR with HRD vs regular Blu Rays, and then 4K HDR - SDR BT.2020 vs Blu Ray. That's how I know my picture is close, since I have my projector dialed in for regular 1080p content. I may do some more comparisons, which is easy with a Blu Ray player and a 4K Blu Ray player in my rack.
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I have done side by side ( more like one, then the other, then back again ) between first 4K BR with HRD vs regular Blu Rays, and then 4K HDR - SDR BT.2020 vs Blu Ray. That's how I know my picture is close, since I have my projector dialed in for regular 1080p content. I may do some more comparisons, which is easy with a Blu Ray player and a 4K Blu Ray player in my rack.
Are you using the Oppo or Panny 900?
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Nobody has a SMPTE 2084 gamma curve measured on a projector?.. Or are you all just eyebaling it.?
I have 0-100% IRE patterns with 10% jumps for grayscale and gamma calibration on a SD card that the player read as a UHD BT2020 HDR source, and i can output it 1080P REC 709 SDR, and see how it responds to the SMPTE 2084 gamma curve that the movies are mastered to.
If someone want the files ill be happy to send a link, so you can post some measurements and move the hole debate to a more objective place.
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Are you using the Oppo or Panny 900?
Panny UB900.
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Panny UB900.
Gotcha. I think the 900+Integral does an excellent job with SDR 2020.
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Gotcha. I think the 900+Integral does an excellent job with SDR 2020.
The Magnificent Seven sure looked good on it last night in 4K.
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Here is 3 HDR Smpte 2084 gamma measurements on a projector calibrated to 14fl, using a UB900 with different settings in the HDR converter, neutral -12 and +12 Its clear that the +12 setting pushes the gamma curve closer to the reference, but it also adds massive white clipping, just as adjusting contrast up on a projector..
This projector is calibrated to a 2.6 Bu ray SDR gamma, now i would imagine that if you do a Blu Ray SDR calibration to a 1.8 or something like that, and shoot 40fl on the scren you will be pretty close to the reference out of black with the converter in neutral setting.. Who have some gamma measurements from brighter projectors.?
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-12 and +12
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But the UHD standard was also delivered with actual specifications on how to do this conversion, unlike converting to SDR with 2020.
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Very interesting. Was this in the form of equations? Have you seen what was this entails?
Thanks for the info.
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Here is some stuff to read about UHD HDR WCG calibration.
http://files.spectracal.com/Documents/White%20Papers/HDR_Demystified.pdf
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Kris should the new JVC models improve this in any way?
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Here is some stuff to read about UHD HDR WCG calibration.
http://files.spectracal.com/Documents/White%20Papers/HDR_Demystified.pdf
Good information in there - thanks !
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Kris should the new JVC models improve this in any way?
Not Kris, but the new JVC models really only have two changes over the current models - low latency ( " gaming " ) mode, and auto HDR plus HLG. But with numerous user mode settings, you can set one up for no HDR and having it map down to standard gamma and REC709 per Kris's suggestion.
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That PDF is neat. At the end it explained the Technicolor HDR which is added to LG OLEDs this year.
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Not Kris, but the new JVC models really only have two changes over the current models - low latency ( " gaming " ) mode, and auto HDR plus HLG. But with numerous user mode settings, you can set one up for no HDR and having it map down to standard gamma and REC709 per Kris's suggestion.
Ah ok, so the new hdr mode doesn't help the projector correctly map hdr levels?
And do I have to do a captcha every time I post in this forum? So far it's two for two...
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Ah ok, so the new hdr mode doesn't help the projector correctly map hdr levels?
And do I have to do a captcha every time I post in this forum? So far it's two for two...
Only for the first few posts. I have approved your first two.
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Ah ok, so the new hdr mode doesn't help the projector correctly map hdr levels?
And do I have to do a captcha every time I post in this forum? So far it's two for two...
Hard to say until someone gets one and tests it. I'm guessing that it will still need some settings adjusted based on your screen size etc.
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Ah ok, so the new hdr mode doesn't help the projector correctly map hdr levels?
And do I have to do a captcha every time I post in this forum? So far it's two for two...
Not after a few posts. I think after three have been approved it stops. I approved your earlier posts.
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Hey Everyone. Just thought I'd chime in with some thoughts and experiments I've been running the last few days. As all are more than aware of here HDR on projection is sort of a work in progress right now. I haven't had the chance to play with HDR with the newer Sony offerings since they've revamped with firmware, so most of these comments are based on my time with the JVC X750. Initially most were using JVC's recommended settings and then going from there using a fleeting amount of test patterns that are available to dial in a picture that looks good. The problem there is while it may look good, it is still a best guess approach at this point derived mainly from trial and error with other's settings or successes. The next step was converting the HDR output to a SDR output but retaining the WCG capacity of the video signal. This seems to work best with the Panasonic player at the moment, but even after many weeks of trial and error I still see issues with gamma, mild clipping and more with this solution. Since the WCG portion of the movie is mastered in relation to the HDR EOTF, I imagine we are still seeing an improper conversion down to SDR levels as you would have to take into account the change in color volume from the intended display luminance. Sure it can look good still, but I would almost argue that the same look could be obtained with standard Blu-ray by just using a wider color preset on the projector. Call me a video snob but I prefer accurate to intent images rather than images that just look good.
So I decided to try something that no one ever seems to consider or try, telling the player NO for HDR and having it map down to standard gamma and REC709 color. This still preserves the resolution bump offered by UHD and the 10-bit video. But the UHD standard was also delivered with actual specifications on how to do this conversion, unlike converting to SDR with 2020. Using this method I get a proper conversion for both gamma and color to SDR, and can view the movie with a proper calibration. I have to say, so far I'm far more impressed with this as the image never has that "it looks great, but there are a few things that still look off". Like everyone else I am hoping that solutions will come that deliver an ACCURATE fold down to SDR with 2020 color, but it appears we are not there yet. I am also anxious to see what can be achieved with a Radiance Pro that tone maps HDR down to the projector's true output in what appears to be a much more intelligent fashion. Until then, I think I'm going to stick with this (other than continuing experimentation with the other options for testing purposes) for now and just sit back and enjoy.
This is the same way I have been doing it from the start as it gives the best and most accurate picture and it is important to me. :)
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So I decided to try something that no one ever seems to consider or try, telling the player NO for HDR and having it map down to standard gamma and REC709 color.
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I know you have been very busy of late, but have you had a chance to evaluate this select SDR for HDR UHD disks?
Also, with BT.2390, don't manufacturers now have a recommendation for how to convert HDR to the display's peak luminance capability? (And does anyone follow that recommendation?)
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I know you have been very busy of late, but have you had a chance to evaluate this select SDR for HDR UHD disks?
Also, with BT.2390, don't manufacturers now have a recommendation for how to convert HDR to the display's peak luminance capability? (And does anyone follow that recommendation?)
With about 10,000 variables for home projection systems and brightness ( and the fact most people don't have light meters and don't have a clue how bright their projector even is ), how would this ever work ? Isn't that for flat panel TV's ?
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With about 10,000 variables for home projection systems and brightness ( and the fact most people don't have light meters and don't have a clue how bright their projector even is ), how would this ever work ? Isn't that for flat panel TV's ?
With a user input of screen gain, and distance to the screen, the jvcs have all the info they need to calculate screen brightness.
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With about 10,000 variables for home projection systems and brightness ( and the fact most people don't have light meters and don't have a clue how bright their projector even is ), how would this ever work ? Isn't that for flat panel TV's ?
Doesn't seem an unreasonable "requirement" to have a light meter to properly calibrate. I mean we already need light meters to set grayscale correctly.
MFG's should be giving us a place to enter "Ypeak" into the projector so that it can intelligently map everything. Heck they could even provide a table (or online, or built-in calculator) with swags for Ypeak based off screen size, gain, throw. It would be better than the nothing that we have now.
Regardless of what you think about HDR for projection, IMO having an external device convert to some intermediate format is a hack, and should not be perpetuated, or relied upon.
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Doesn't seem an unreasonable "requirement" to have a light meter to properly calibrate. I mean we already need light meters to set grayscale correctly.
MFG's should be giving us a place to enter "Ypeak" into the projector so that it can intelligently map everything. Heck they could even provide a table (or online, or built-in calculator) with swags for Ypeak based off screen size, gain, throw. It would be better than the nothing that we have now.
Regardless of what you think about HDR for projection, IMO having an external device convert to some intermediate format is a hack, and should not be perpetuated, or relied upon.
With the RS4500 I no longer need the HD Fury Integral !
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With the RS4500 I no longer need the HD Fury Integral !
And with a pretty minor firmware update, those of us with RS500/600s, wouldn't need the fury either!
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And with a pretty minor firmware update, those of us with RS500/600s, wouldn't need the fury either!
It was pretty much " set and forget " for me though, so it wasn't a problem anyway.