F8500 Recommended Settings Thread..... - Page 81 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #2401 of 2411 Old 09-20-2014, 10:17 PM
AVS Special Member
 
fierce_gt's Avatar
 
Join Date: Sep 2008
Posts: 3,839
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 535 Post(s)
Liked: 817
Quote:
Originally Posted by Stereodude View Post
IMHO, you want to send 0-255 RGB. If it was sending YCrCb it would need to send 16-235.

If you can change it to 16-235 RGB you'll lose brightness since you can only adjust the bottom side of that, and can't stretch 235 up to white.
I'm not sure I understand. 'white' is the peak level of the tv. if the tv is expecting a 16-235 signal, then 235 will be white, and anything above that won't be any brighter.


it's not about getting the most levels, it's about matching the display to the source, and currently video is 16-235, so that's what you want to use for it.


for what it's worth, there's a bunch of stuff that does 16-255 though, for whatever reason. often called something like 'superwhite'.

Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1018AH, 5.1 audio
Sources: HTPC(Mediabrowser), PS3, XBOX360, Wii, Sony DVP-CX995V
Control: Harmony One
fierce_gt is offline  
Sponsored Links
Advertisement
 
post #2402 of 2411 Old Yesterday, 05:11 AM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,955
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 526 Post(s)
Liked: 549
Quote:
Originally Posted by fierce_gt View Post
I'm not sure I understand. 'white' is the peak level of the tv. if the tv is expecting a 16-235 signal, then 235 will be white, and anything above that won't be any brighter.
If you send YCrCb the TV expects 16-235 and will expand it internally to 0-255 when converting color spaces. If you send RGB, the TV expects 0-255. However, should you choose to send 16-235 RGB (for some strange reason) you can choose low and get your back your blacks (not sure if it's through shifting or expansion). However, AFAIK, the TV will not expand/stretch the 235 white in the input to 255 white (what it displays). This means your input signal does not map properly to what the panel displays.
Stereodude is online now  
post #2403 of 2411 Old Yesterday, 09:05 AM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,955
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 526 Post(s)
Liked: 549
Here's an admittedly less than stellar picture but it will still help visualize the issue.



My HTPC is sending the TV a RGB format signal via HDMI. MPC-HC is playing the video at 16-235. HDMI black level is set to low. Black looks fine, but look at what 235 looks like vs. white. I put a box of 255,255,255 white to the right. What should be 100IRE "white" in the video signal is a nice shade of gray. There's no setting or adjustment in the F8500 that will correct the whites. 16-235 RGB is a big no-no for the F8500.
Attached Thumbnails
Click image for larger version

Name:	16-235RGB_HDMI_low.jpg
Views:	108
Size:	134.7 KB
ID:	273241  
Stereodude is online now  
post #2404 of 2411 Old Yesterday, 09:20 AM
AVS Special Member
 
zoyd's Avatar
 
Join Date: Sep 2006
Location: Planet Dog
Posts: 4,558
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Liked: 329
235 only looks bad in that picture because you have a 255 background (our eyes adjust to the brightest white available). If you had all 235s showing on each display is would look pure white. In general it is a bad idea to push "100% = reference white" up to the peak value your display can produce because you'll usually run into one of the color channels clipping. Typical set-ups map video level in 16-235 -> 16-235 as well as full range RGB-> 16-235, the only difference is that with video levels you preserve access to WTW and with full range RGB you don't.

-----

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
zoyd is online now  
post #2405 of 2411 Old Yesterday, 09:23 AM
AVS Special Member
 
fierce_gt's Avatar
 
Join Date: Sep 2008
Posts: 3,839
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 535 Post(s)
Liked: 817
Quote:
Originally Posted by Stereodude View Post
If you send YCrCb the TV expects 16-235 and will expand it internally to 0-255 when converting color spaces. If you send RGB, the TV expects 0-255. However, should you choose to send 16-235 RGB (for some strange reason) you can choose low and get your back your blacks (not sure if it's through shifting or expansion). However, AFAIK, the TV will not expand/stretch the 235 white in the input to 255 white (what it displays). This means your input signal does not map properly to what the panel displays.
maybe it's the 16-235 rgb that's confusing me, not sure. but when I display video I get the same peak brightness as when I display games.


I've calibrated my display for both video and gaming, and I get basically the same image as long as both the source and display are set to the same range.


as Zoyd commented above, what you're showing isn't really evidence that 235 is more dim than 255. I would also add that it's just showing you've calibrated for white to be higher than 235. I didn't want 50ftl, so my test patterns do look like that, in order to get 'white' no brighter than 32ftl, there's obviously a lot of wtw info that could be displayed by the display.
but, when I play games, and have 0-255 sent to the display, and switch it to 'normal' I STILL have 32ftl for whites.


if I wanted to get peak brightness from the display for video, I would adjust the contrast so that the bars don't flash above 235. most ppl don't set it that high, but that's a choice, not a limitation

Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1018AH, 5.1 audio
Sources: HTPC(Mediabrowser), PS3, XBOX360, Wii, Sony DVP-CX995V
Control: Harmony One

Last edited by fierce_gt; Yesterday at 09:29 AM.
fierce_gt is offline  
post #2406 of 2411 Old Yesterday, 09:46 AM
AVS Special Member
 
zoyd's Avatar
 
Join Date: Sep 2006
Location: Planet Dog
Posts: 4,558
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Liked: 329
TVs do not typically expand input 235 to the peak value of the internal signal processor (usually 10-bit 1023), this is to preserve the headroom (WTW) in video reproduction specifications. When sending full range 0-255 it will actually compress this back to 64-940 internally.

-----

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
zoyd is online now  
post #2407 of 2411 Old Yesterday, 10:04 AM
AVS Special Member
 
fierce_gt's Avatar
 
Join Date: Sep 2008
Posts: 3,839
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 535 Post(s)
Liked: 817
Quote:
Originally Posted by zoyd View Post
TVs do not typically expand input 235 to the peak value of the internal signal processor (usually 10-bit 1023), this is to preserve the headroom (WTW) in video reproduction specifications. When sending full range 0-255 it will actually compress this back to 64-940 internally.
so I'm seeing the same image on screen with 16-235/low and 0-255/normal not because the white in 235 is being brought up to the max of 255, but because the white of the 255 is being brought down to the max of 235?


haha, either way, I think the important thing is matching source to display. it's not like the f8500 isn't way too bright for most situations anyway. it's got plenty of brightness with a video signal

Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1018AH, 5.1 audio
Sources: HTPC(Mediabrowser), PS3, XBOX360, Wii, Sony DVP-CX995V
Control: Harmony One
fierce_gt is offline  
post #2408 of 2411 Old Yesterday, 10:11 AM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,955
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 526 Post(s)
Liked: 549
Quote:
Originally Posted by zoyd View Post
235 only looks bad in that picture because you have a 255 background (our eyes adjust to the brightest white available). If you had all 235s showing on each display is would look pure white. In general it is a bad idea to push "100% = reference white" up to the peak value your display can produce because you'll usually run into one of the color channels clipping. Typical set-ups map video level in 16-235 -> 16-235 as well as full range RGB-> 16-235, the only difference is that with video levels you preserve access to WTW and with full range RGB you don't.
So I put the meter to the panel and you are correct. 235 with HDMI black level = low is the same ~170nits that you get with 255 with HDMI black level = normal. However, if you set HDMI black level = low and output 255 you can get ~205nits with a dE of .8. That's with the panel in Dark Room. Changing to Bright Room you get 226nits, but the panel becomes red deficient and you get a dE of 5.6. So, it seems you could get some extra brightness out of the panel in Dark Room if you set MadVR to output Custom 16-255, set the F8500 to HDMI black level = low and calibrated accordingly.

Quote:
Originally Posted by fierce_gt View Post
as Zoyd commented above, what you're showing isn't really evidence that 235 is more dim than 255. I would also add that it's just showing you've calibrated for white to be higher than 235. I didn't want 50ftl, so my test patterns do look like that, in order to get 'white' no brighter than 32ftl, there's obviously a lot of wtw info that could be displayed by the display.
No, I didn't calibrate for white to be higher than 235. What I showed is there is some extra luminance capability to be had in "Dark room".
Stereodude is online now  
post #2409 of 2411 Old Yesterday, 10:12 AM
AVS Special Member
 
zoyd's Avatar
 
Join Date: Sep 2006
Location: Planet Dog
Posts: 4,558
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Liked: 329
Quote:
Originally Posted by fierce_gt View Post
so I'm seeing the same image on screen with 16-235/low and 0-255/normal not because the white in 235 is being brought up to the max of 255, but because the white of the 255 is being brought down to the max of 235?
Yes, if you have the display input set properly all input ranges get mapped to the same 10-bit display range -> 64:940. You can change that through service menu tweaks (ADC calibration) but there is no need to.

-----

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
zoyd is online now  
post #2410 of 2411 Old Yesterday, 10:27 AM
AVS Special Member
 
fierce_gt's Avatar
 
Join Date: Sep 2008
Posts: 3,839
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 535 Post(s)
Liked: 817
Quote:
Originally Posted by Stereodude View Post
So I put the meter to the panel and you are correct. 235 with HDMI black level = low is the same ~170nits that you get with 255 with HDMI black level = normal. However, if you set HDMI black level = low and output 255 you can get ~205nits with a dE of .8. That's with the panel in Dark Room. Changing to Bright Room you get 226nits, but the panel becomes red deficient and you get a dE of 5.6. So, it seems you could get some extra brightness out of the panel in Dark Room if you set MadVR to output Custom 16-255, set the F8500 to HDMI black level = low and calibrated accordingly.

No, I didn't calibrate for white to be higher than 235. What I showed is there is some extra luminance capability to be had in "Dark room".
sorry, wrong word. I should have said 'peak luminance' instead of 'white'. or that you've calibrated white(235) to be a lower luminance than the tv is capable of(this is what I have done).


I can see why you'd get a higher luminance when sending the tv 255 when it's in 'low', since it seems to maintain a decent amount of wtw headroom no matter what. the question is, is that actually good? cause I'm thinking it's less accurate. some displays have a 16-255 option, usually called something like 'superwhite', but I've never really liked how that looks.


does content often have wtw signals encoded? I'm still definitely confused by the different ranges, so I try to keep things simple by just keep all my video at 16-235 and games at 0-255

Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1018AH, 5.1 audio
Sources: HTPC(Mediabrowser), PS3, XBOX360, Wii, Sony DVP-CX995V
Control: Harmony One
fierce_gt is offline  
post #2411 of 2411 Old Yesterday, 10:37 AM
AVS Special Member
 
zoyd's Avatar
 
Join Date: Sep 2006
Location: Planet Dog
Posts: 4,558
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 141 Post(s)
Liked: 329
Quote:
Originally Posted by Stereodude View Post
So, it seems you could get some extra brightness out of the panel in Dark Room if you set MadVR to output Custom 16-255, set the F8500 to HDMI black level = low and calibrated accordingly.
Yes, this is equivalent to adjusting the input ADC to exercise codes above 235 and should preserve the correct black level. You still have to be careful of clipping (check your color clipping patterns) but it would be perfectly reasonable to set madVR to say 16-245 to get some extra brightness and still maintain a bit of headroom.

-----

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
zoyd is online now  
Reply Plasma Flat Panel Displays

Tags
Samsung Pn51f8500 51 Inch 3d Smart Plasma Hdtv
Gear in this thread - Pn51f8500 by PriceGrabber.com

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off