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I have a 50" 800u Panasonic plasma and use it about 90% of the time for gaming and love how it looks in every regard with it set to thx. My only problem is alot of times with games, it looks a bit muddy.


I would really appreciate if someone could explain where the gamma adjust is in the service menu. I know how to access the SM and needless to say, understand the dangers of it, which is why I'm asking instead of going in blindly. I've already adjusted the red to make it a bit more red and less pink but just cannot find the gamma. Thanks!
 

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Quote:
Originally Posted by Chad B /forum/post/15523349


There is no gamma adjustment for these in the SM. You just have your choice of THX mode, which has good gamma, and the other modes, which do not.

The gamma only seems "good" if you look at a single gamma number for the entire luminance range. If you look at the gamma for each step on the grayscale, you get low gamma at lower luminance levels and high gamma at high luminance levels. That contributes to the flat dull look of the THX mode compared to panels with a reasonable gamma for each grayscale step. Some, like the original poster, might say the THX mode is "muddy" because the darker steps are too light... the lighter steps are too dark which contributes to the dull look. Adding luminance to try to overcome the dull look doesn't make it go away either.
 

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Quote:
Originally Posted by Doug Blackburn /forum/post/15529748


The gamma only seems "good" if you look at a single gamma number for the entire luminance range. If you look at the gamma for each step on the grayscale, you get low gamma at lower luminance levels and high gamma at high luminance levels. That contributes to the flat dull look of the THX mode compared to panels with a reasonable gamma for each grayscale step. Some, like the original poster, might say the THX mode is "muddy" because the darker steps are too light... the lighter steps are too dark which contributes to the dull look. Adding luminance to try to overcome the dull look doesn't make it go away either.

My calibration results on many 800u's disagree, not with the character you describe, but at least with the lack of "goodness".

I get, after proper white and black level calibration, a gamma of 2.05 at the low end to 2.3 in the upper middles. While this is not perfect, it is well above average. Better, in fact, than any plasma I can think of except the Pioneers.

Here is a calibration report of an 800u in THX mode.

Check the point gamma chart.
 

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Quote:
Originally Posted by Chad B /forum/post/15529967


My calibration results on many 800u's disagree, not with the character you describe, but at least with the lack of "goodness".

I get, after proper white and black level calibration, a gamma of 2.05 at the low end to 2.3 in the upper middles. While this is not perfect, it is well above average. Better, in fact, than any plasma I can think of except the Pioneers.

Here is a calibration report of an 800u in THX mode.

Check the point gamma chart.

Same here. In fact, my 58" 800U (manufacture date = December 2008) has an even better gamma after the 100 hour break-in. It's pretty linear at 2.25-2.3 from 10-60IRE, then peaks to 2.4 around 70IRE and falls back to 2.3 at 80-100IRE. See here:



My grayscale in WARM mode was initially too warm. So rather than bringing RDRV down in the SM, I brought GDRV and BDRV up. As a consequence, my THX mode light output increased from 31 ftL to 35 ftL with PICTURE at 100. Basically, by driving the RGB higher it effectively increases the light output. I found light output to be too low in THX mode even with PICTURE at 100. That might be the reason the OP is finding it "muddy".
 

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Quote:
Originally Posted by daMaster /forum/post/15530016


Same here. In fact, my 58" 800U (manufacture date = December 2008) has an even better gamma after the 100 hour break-in. It's pretty linear at 2.25-2.3 from 10-60IRE, then peaks to 2.4 around 70IRE and falls back to 2.3 at 80-100IRE. See here:



My grayscale in WARM mode was initially too warm. So rather than bringing RDRV down in the SM, I brought GDRV and BDRV up. As a consequence, my THX mode light output increased from 31 ftL to 35 ftL with PICTURE at 100. Basically, by driving the RGB higher it effectively increases the light output. I found light output to be too low in THX mode even with PICTURE at 100. That might be the reason the OP is finding it "muddy".

I agree; that has been my strategy as well. I like more than 30-31 ftL also. Though I have been averaging closer to 33 ftL after cal, that is more than explainable by sample to sample differences and differences in meters. I suspect the gamma difference can be attributed to those 2 things as well.
 

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Quote:
Originally Posted by Chad B /forum/post/15529967


My calibration results on many 800u's disagree, not with the character you describe, but at least with the lack of "goodness".

I get, after proper white and black level calibration, a gamma of 2.05 at the low end to 2.3 in the upper middles. While this is not perfect, it is well above average. Better, in fact, than any plasma I can think of except the Pioneers.

Here is a calibration report of an 800u in THX mode.

Check the point gamma chart.


Samsung plasmas have 7 Gamma steps to choose from in the User Menu and the Service Menu will move the range of those 7 steps up and down. Furthermore, Samsung doesn't play games with lower gamma at low luminance and higher gamma at higher luminance levels. You can setup a Samsung panel to have a gamma as high as 2.7 if you want to... and it will measure very close to 2.7 at each grayscale step (perhaps not 10% though, crush may be creeping in at that point). I'm certainly not advocating DOING that, but it's quite possible. 2.3 or so seems to be a good setting for watching Blu-ray movies in a dark room. Side-by-side with an 800U in THX mode, with both panels calibrated, the Samsung will have more accurate color, lack the muddy/flat/dull appearance, and there won't be an obvious grayscale error at 80% that just about every 800U has. The A550 Samsung won't look quite as black as the 800U, but the A650 Samsung is a pretty close match for the black level of the 800U.


Last night I used a Lumagen Radiance XD to produce the same sort of gamma performance exhibited by the 800U in THX mode and found it upset the images in exactly the same way I object to in the 800U's THX mode. I used a Samsung plasma and a Toshiba LCD just to see what would happen with 2 different panels and 2 different technologies. I copied the results I've gotten from 800U calibrations.


There have been a lot of AVS Forum 800U owners who have the same complaint about THX mode... muddy and/or flat/dull. I've had calibration calls from at least 10 people wanting to know if I can remove the flat-dull look of the THX mode in their 800U and I had to be honest... no, there's nothing that can be done to eliminate it. Half of those calibrations were "lost" because of the inability to eliminate that gamma issue. You can futz with the cuts & gains to move the average gamma for the 800U up and down a little, but you can never remove the characteristic low gamma at low luminance, and high gamma at high luminance problem. The spread from 2.05 to 2.4 is HUGE - and to me it compomises the images far too much. When I see these panels I'm torn between using a 1.95-2.3 range or going a little higher (your 2.05-2.4 range for example). I'll take a Samsung A650 plasma any day over an 800U - with calibration, you can have nearly perfect primaries and secondaries, any gamma setting you want (without much variation from low to high luminance), and grayscale performance about on par with the 800U.
 

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Quote:
Originally Posted by Doug Blackburn /forum/post/15533380


Samsung plasmas have 7 Gamma steps to choose from in the User Menu and the Service Menu will move the range of those 7 steps up and down. Furthermore, Samsung doesn't play games with lower gamma at low luminance and higher gamma at higher luminance levels. You can setup a Samsung panel to have a gamma as high as 2.7 if you want to... and it will measure very close to 2.7 at each grayscale step (perhaps not 10% though, crush may be creeping in at that point). I'm certainly not advocating DOING that, but it's quite possible. 2.3 or so seems to be a good setting for watching Blu-ray movies in a dark room. Side-by-side with an 800U in THX mode, with both panels calibrated, the Samsung will have more accurate color, lack the muddy/flat/dull appearance, and there won't be an obvious grayscale error at 80% that just about every 800U has. The A550 Samsung won't look quite as black as the 800U, but the A650 Samsung is a pretty close match for the black level of the 800U.

What grayscale error at 80%? My grayscale is linear and tracks excellent from 20-100IRE and there's no discrepancy or error at 80IRE. My gamma curve posted above is not perfectly linear, but it's damn close. I don't find the post-calibrated THX mode to be muddy/flat/dull at all. In fact, with an average gamma of 2.31 (as reported by ColorHCFR), the colors are so vibrant and pop out of the screen. Black levels are so deep it feels like looking through a clear glass window at live imagery. Don't know if this "issue" you're referring to was with early production 800Us, but mine has a Dec. 2008 manufacturing date and doesn't exhibit ANY of the issues you're describing.


And to compare the black levels of a Samsung 550 to the 800U is ridiculous. I've calibrated the 550 and the difference is very noticeable. The 800U comes close to Pioneer Kuro performance. The Samsung really doesn't. I haven't seen the 650, but Samsung would have to have made a great leap in black levels from the 550 to the 650 to come close to the 800U. By account of almost all the reviews out there, that doesn't seem to be the case, but I'll believe what you say when I see it (i.e. 800U vs 650).
 

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Quote:
Originally Posted by Doug Blackburn /forum/post/15533380


Samsung plasmas have 7 Gamma steps to choose from in the User Menu and the Service Menu will move the range of those 7 steps up and down. Furthermore, Samsung doesn't play games with lower gamma at low luminance and higher gamma at higher luminance levels. You can setup a Samsung panel to have a gamma as high as 2.7 if you want to... and it will measure very close to 2.7 at each grayscale step (perhaps not 10% though, crush may be creeping in at that point). I'm certainly not advocating DOING that, but it's quite possible. 2.3 or so seems to be a good setting for watching Blu-ray movies in a dark room. Side-by-side with an 800U in THX mode, with both panels calibrated, the Samsung will have more accurate color, lack the muddy/flat/dull appearance, and there won't be an obvious grayscale error at 80% that just about every 800U has. The A550 Samsung won't look quite as black as the 800U, but the A650 Samsung is a pretty close match for the black level of the 800U.

The other point worth mentioning is if you're comparing the 50" versions of the 800U to the 50" versions of the Samsung 550/650. I have the 58" 800U. OP has the 50", and maybe that model has the muddy/flat/dull look.
 

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Quote:
Originally Posted by seiken910 /forum/post/15520680


I have a 50" 800u Panasonic plasma and use it about 90% of the time for gaming and love how it looks in every regard with it set to thx. My only problem is alot of times with games, it looks a bit muddy.


I would really appreciate if someone could explain where the gamma adjust is in the service menu. I know how to access the SM and needless to say, understand the dangers of it, which is why I'm asking instead of going in blindly. I've already adjusted the red to make it a bit more red and less pink but just cannot find the gamma. Thanks!

You may want to give my user menu and service menu settings a go as detailed in this post: http://www.avsforum.com/avs-vb/showp...postcount=2049 . Be aware though that I have a 58" version of the PZ800U.
 

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Quote:
Originally Posted by daMaster /forum/post/15533736


The 800U comes close to Pioneer Kuro performance.

Whoa, I was with you until here. The Panny has a better black level than the Samsung, but it is not even close to the current generation Kuro, which is close to being so low it is unmeasurable.
 

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Quote:
Originally Posted by TomHuffman /forum/post/15562141


Whoa, I was with you until here. The Panny has a better black level than the Samsung, but it is not even close to the current generation Kuro, which is close to being so low it is unmeasurable.

You're right. I should rephrase that: the 800U is the next best thing after the Kuro for black level performance.


Unfortunately, I've only had the opportunity to calibrate and do dark-room testing of the 800U and Samsung 550. I'd like to have a go with the Samsung 650, Kuro (non-Elite), and Kuro Elite for the sake of comparison. But I'd be surprised if the Samsung 650 has the same black levels as the 800U, because that would be a significant leap from the 550.
 

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Tom Huffman calibrated my 50" 800U several months ago and here is the gamma curve post-calibration in the THX (warm) setting:


10%--2.22

20%--2.24

30%--2.26

40%--2.29

50%--2.34

60%--2.39

70%--2.32

80%--2.30

90%--2.32

100%-2.30


Not perfectly linear, but pretty damn good, IMO. There is nothing "washed out" about my picture, something that I couldn't say before he calibrated it. Several months post-calibration, the colors remain accurate and vibrant, with plenty of "pop" and excellent picture depth.


I couldn't be happier with the 800U and the job that Tom did. The change from the pre-calibration THX setting was so dramatic that I went through a day or two of "what happened to my set?"....followed by "oh, yea!". My wife--a professional photographer--saw the improvement immediately and remains impressed by what Tom was able to do for the set. I have had no reason to deviate more than one or two ticks from the user's menu settings that Tom gave me after he worked his magic in the service menu.
 

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Quote:
Originally Posted by baldino /forum/post/15567868


Tom Huffman calibrated my 50" 800U several months ago and here is the gamma curve post-calibration in the THX (warm) setting:


10%--2.22

20%--2.24

30%--2.26

40%--2.29

50%--2.34

60%--2.39

70%--2.32

80%--2.30

90%--2.32

100%-2.30


Not perfectly linear, but pretty damn good, IMO. There is nothing "washed out" about my picture, something that I couldn't say before he calibrated it. Several months post-calibration, the colors remain accurate and vibrant, with plenty of "pop" and excellent picture depth.


I couldn't be happier with the 800U and the job that Tom did. The change from the pre-calibration THX setting was so dramatic that I went through a day or two of "what happened to my set?"....followed by "oh, yea!". My wife--a professional photographer--saw the improvement immediately and remains impressed by what Tom was able to do for the set. I have had no reason to deviate more than one or two ticks from the user's menu settings that Tom gave me after he worked his magic in the service menu.

Your gamma values confirm that the 50" version of the PZ800U like the 58" version has a nearly linear gamma. I have no idea what Doug Blackburn is talking about and none of his claims were backed with data/facts.


I re-tweaked my set a little bit and my average gamma is now 2.29. Here are my gamma values from 10-90IRE:

10%: 2.25

20%: 2.25

30%: 2.26

40%: 2.30

50%: 2.29

60%: 2.32

70%: 2.40

80%: 2.28

90%: 2.27


Here's my latest gamma chart from ColorHCFR:

 

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Quote:
Originally Posted by Chad B /forum/post/15571183


None of my claims were backed up with data/facts? Really? My claims were that gamma is "good" in THX mode, not very good in other modes; and I posted a calibration report that shows a decent gamma response in THX mode that varies between 2.05 and 2.3. Aren't you getting me mixed up with another poster?

Oops, I meant Doug Blackburn. I've edited my post above with the correction. Sorry.
 

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Quote:
Originally Posted by Chad B /forum/post/15571183


None of my claims were backed up with data/facts? Really? My claims were that gamma is "good" in THX mode, not very good in other modes; and I posted a calibration report that shows a decent gamma response in THX mode that varies between 2.05 and 2.3. Aren't you getting me mixed up with another poster?

My ISF calibrator(Bill Hergonson-Coast Calibration) sent me a heads up that you guys are the authorities on calibration so I'll tread lightly, what about my Custom mode post calibration gamma-seems linear and high enough to me? Here's a direct link to the gamma numbers/graph:



Also, Bill said my set's color matrix was close to being right on(especially the important blue point.)



Btw, 37.72ftL seems perfect to me-plenty bright during daylight hours, and just right at night(absolute match for BD 24p in a totally dark room.)
 

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Quote:
Originally Posted by JohnES1 /forum/post/15571538


My ISF calibrator(Bill Hergonson-Coast Calibration) sent me a heads up that you guys are the authorities on calibration so I'll tread lightly, what about my Custom mode post calibration gamma-seems linear and high enough to me? Here's a direct link to the gamma numbers/graph:



Also, Bill said my set's color matrix was close to being right on(especially the important blue point.)



Btw, 37.72ftL seems perfect to me-plenty bright during daylight hours, and just right at night(absolute match for BD 24p in a totally dark room.)

Hmm, that isn't bad at all. While not perfect, that gamma should look pretty good. I'm surprised you got that in Custom mode, as the 800u's I've worked with had poor gamma in any mode but THX. Do you know if your calibrator took that final reading in the service menu or out of the service menu?

I like light output in that range also (upper 30's).
 
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