AVS Discussions

UHD on CRT.

UHD on CRT.
« on: December 31, 2016, 06:08:28 AM »
If you have a reason why its a good idea to use the UHD media, or why not to use it on a CRT post about it here.

Everywhere i see it mentioned its comes with the idea to run 48hz.. Now 48hz is  god awfull, flickering anoying framerate on crt, so for a higher resolution to make sense i think it should be to create something better than what we have now.

So how to use the UHD format to rise the image fedility of CRT.?
The old BLACK IS Back..!!

alangouger

  • *****
  • 40
  • My avatar, thats me in my bat cave theater.
Re: UHD on CRT.
« Reply #1 on: January 02, 2017, 09:07:01 AM »
I would think using a UHD player into the HDFury "Linker" going through a Moomi card would get HDR 10 or 12 deep color into a CRT projector at 1080P resolution. It has been years for me and CRT can a CRT deliver 10 or 12 bit to the screen? If so you should be golden.

Re: UHD on CRT.
« Reply #2 on: January 02, 2017, 09:47:35 AM »
I would think using a UHD player into the HDFury "Linker" going through a Moomi card would get HDR 10 or 12 deep color into a CRT projector at 1080P resolution. It has been years for me and CRT can a CRT deliver 10 or 12 bit to the screen? If so you should be golden.

You dont need a linker to get deap color, its suported by any HD display, so its no problem feeding the moome card 1080P 4:4:4 12bit.

The problem as i se it with UHD is the gamma, and the light output of the CRT, i have been running UHD on My Marquee, downscaled from my Panasonic UB900, but there is no way i can get it to display anything that i will prefer over HD Blu ray.

And im not really sure that the 10bit resolution on UHD discs actually give anything, as its stretched over a much wider color gammuth, and around 20x or more light output, and as we limit it to REC 709 and compress the highlight area of the HDR i think 8bit HD blu ray has a equally effective graduation.

If we ever get DV HDR on UHD disc, we might get closer to a usefull HDR format for projectors.. As i see it we curently need around 60+fl/200+nit to do UHD SDR, if we stick to the HDR to SDR converted/ compressed output of the UB900 at neutral setting, and compensating by adjusting the converter, it add white clipping, and im not willing to give a lot to get some.. It has to be a overall better image with no obvious errors, as we have a very close to perfect HD Blu ray reproduction with a matching, native gamma response in the projector, and a dynamic range match.

I know there is a gain to UHD SDR if you can hold a perfect black and a 60fl output, but no CRT will ever get there, i dont even know of any Digital projectors capable.
« Last Edit: January 02, 2017, 09:51:41 AM by stridsvognen »
The old BLACK IS Back..!!

alangouger

  • *****
  • 40
  • My avatar, thats me in my bat cave theater.
Re: UHD on CRT.
« Reply #3 on: January 03, 2017, 02:53:14 AM »
i dont even know of any Digital projectors capable.

Possibly a dual projection system to expand the dynamic range similar to what Dolby Vision and SIM2 are doing.

I can understand the concern with HD10 via a CRT projector. Out of curiosity have you tried HD10 scaled to 1080p ( Linker needed ) and choosing a linear gamma of say 3.6 to 3.9 this would maintain the 100ire of standard SD/HD and help maintain the light typically loss due to the HDR EOTF, in theory of course, I do not have a CRT to experiment with.

A UHD HDR player set to HD ( I think that is what you are doing ) should still yield some befits ( title dependent ) over standard blu-ray so not all is lost.
« Last Edit: January 03, 2017, 02:55:57 AM by alangouger »

Re: UHD on CRT.
« Reply #4 on: January 03, 2017, 04:22:55 AM »
Im curious what using the linker should do to help compensating for the lack of light output, as it looks to me the SDR convertion is to help maintain a decent average light output, folowing the SMPTE 2084 up to around 70% ire where the converter breaks the curve and compresses the 70-100% IRE of the UHD HDR.

I can take the radiance and shape the gamma curve forcing it to follow the SMPTE 2084 as long as possible, but as it looks to me 10-14fl just dont cut it very well, and my average image will still look dim as the UHD movies are mastered to SMPTE 2084 / static HDR10.

So as i seen it for now it is all lost on a CRT.. Oposit on my old Pioneer Plasma, cranking that one all up, maintaining black, and make it track Smpte 2084 from 0-70% IRE it sure show what there is to want from the UHD HDR discs.. but it takes 60fl/200 nit for me to get there, and i normaly run that screen around 18fl for normal HD Blu ray.

Sure i can stack 4 CRT projectors, or more, but that just degrade the rest of the image more, so for image fedility on CRT i think we for now are stuck with HD Blu ray, wich we dont need all sorts of image degrading processing convertion and manipulation to display.. Its just a player into a DAC and its roling.. My experience is that most of the time less is more, and more is less.. That for sure apply to a videochain digital and analog..

But im still open to try new ways, and i would like to benefit from the extra low level details mastered on the UHD discs, as they seem to clip that out of the HD masterings, but ill need a bit more specifik examples, and if you have a OLED or plasma you should be able to simulate the crt, just limit the light output to around 10-14fl..
Ill try show how the Marquee tracks the SMPTE 2084 with 14fl tonight, using the UB900 1080P SDR out from a UHD HDR source.

If simulating it on a different display, keep in mind that the the CRT have a native gamma around 2.6
« Last Edit: January 03, 2017, 04:58:17 AM by stridsvognen »
The old BLACK IS Back..!!

Re: UHD on CRT.
« Reply #5 on: January 03, 2017, 05:13:53 AM »
I found a normal CRT calibration, and put it into a SMPTE 2084 gamma, not 100% sure that is right, but ill expect it to be pretty close.

The old BLACK IS Back..!!

alangouger

  • *****
  • 40
  • My avatar, thats me in my bat cave theater.
Re: UHD on CRT.
« Reply #6 on: January 04, 2017, 06:45:05 AM »
Using the Linker will alow you to maintain 12 bit deep color setting the output of the player to 1080p does not.
I do not have a CRT for testing so my comments are theory based on my experience so far with HD10. I have to take your word that HD10 via CRT projection is to dim, I would think CRT would be the perfect platform to how off HDR. OLED would be the next closest display to CRT and not as bright as LED or Lcos but it shows the best HDR to date. Maybe Dolby will fair better. Glad to see someone give HDR a try, good work.

AVSCraig

  • *****
  • 1316
  • Home Theater Lover / Sales / Advice
    • AV Science, Inc
Re: UHD on CRT.
« Reply #7 on: January 04, 2017, 07:38:54 AM »
Using the Linker will alow you to maintain 12 bit deep color setting the output of the player to 1080p does not.
I do not have a CRT for testing so my comments are theory based on my experience so far with HD10. I have to take your word that HD10 via CRT projection is to dim, I would think CRT would be the perfect platform to how off HDR. OLED would be the next closest display to CRT and not as bright as LED or Lcos but it shows the best HDR to date. Maybe Dolby will fair better. Glad to see someone give HDR a try, good work.

My JVC RS600 doesn't seem bright enough for HDR, let alone a CRT projector ! 
Direct (585) 671-2972   craig@avscience.com
www.avscience.com
We carry projectors, screens, speakers, receivers etc. !!
Twitter - @AVS_Craig

Re: UHD on CRT.
« Reply #8 on: January 04, 2017, 08:30:09 AM »
The player will output 8-10-12 bit to any display linker or not, it wont output BT 2020 and HDR.

Right now im feeding my Pioneer plasma 1080P SDR RGB 12bit from the UB900, but as earlier i doubt if the 10 bit on UHD discs have finer graduations in practice, as its stretched over a much bigger light span and color gammut.. AS looks to me it seems its not enought to match 8 bit HD blu ray graduation.

CRT used right have much les bit degradation than digital displays, who always seems to introduce errors when remapping/ process the content to behave on the panels.
« Last Edit: January 04, 2017, 08:32:16 AM by stridsvognen »
The old BLACK IS Back..!!

alangouger

  • *****
  • 40
  • My avatar, thats me in my bat cave theater.
Re: UHD on CRT.
« Reply #9 on: January 05, 2017, 05:42:14 AM »
My JVC RS600 doesn't seem bright enough for HDR, let alone a CRT projector !

Craig I know several people watching UHD on their lamp based JVC, Im sure they all want more light but they still enjoy UHD. We all know screen size plays a roll what screen width are you running.

Re: UHD on CRT.
« Reply #10 on: January 05, 2017, 07:36:44 AM »
I think at the end of the day its all opinions.. We know what it takes to do HDR10.. the specs are pretty clear about that, what people like dont like or accept is another thing.. And the general idea about new is always better do have quite a lot of power over peoples opinions.
« Last Edit: January 05, 2017, 08:02:51 AM by stridsvognen »
The old BLACK IS Back..!!

Re: UHD on CRT.
« Reply #11 on: January 08, 2017, 05:01:11 PM »
Here is some Smpte 2084 measurements of my Marquee calibrated to a 2.6 gamma and 14fl
Its UHD HDR testpatterns output at 1080P REC 709 SDR from the UB900 neutral -12 and +12  on the HDR converter settings.

The +12 add crazy white clipping, and the -12 ill guess is pretty much the converter turned off, so i dont see that the converter can be adjusted other than to the negative side for a display that might be to bright for the neutral setting, ill emagine something like a OLED display that shoot 600nit it would be handy to compensate for the missing 400nit

But as i max out below 50nit on the CRT that dont do much good.
The old BLACK IS Back..!!

Re: UHD on CRT.
« Reply #12 on: January 08, 2017, 05:02:00 PM »
-12 and +12
The old BLACK IS Back..!!

Re: UHD on CRT.
« Reply #13 on: January 17, 2017, 12:16:10 PM »
I know there is a gain to UHD SDR if you can hold a perfect black and a 60fl output, but no CRT will ever get there, i dont even know of any Digital projectors capable.

There are many digitals that can achieve 60fl on a normal size screen, but HDR on projectors is a joke even with this kind of light output and the way to go so far is just do rec.709, SDR and keep the resolution and 10bit.
Regards
Andreas                                                           

Calibration software: Lightspace and Calman. TPG: Murideo Fresco SIX-G
Meters: Klein K-10 A and Jeti 1501. THX II certified.