The Official Panasonic 12G Settings/Issues Thread - Page 139

Originally Posted by Meteor|WAR

I just had the exact same issue, see my recent posts in this thread.

In THX mode my G10 does 2.08 gamma (about 29 ftL) when I use the AVS HD 709 to set brightness but looks really good. I get the proper 2.2 gamma if I use the method described here but it looks too dim/lifeless:



I concluded to say the hell with 2.2 gamma. It just doesn't look right on my G10. I think with some TV's you're better off just setting brightness with a pluge pattern.

Originally Posted by LarryInRI

Using the 0.65% method to set brightness only works if the gamma of your TV is 2.22 to start with. It doesn't work in reverse. Use the pluge method.

Larry

Originally Posted by Meteor|WAR

I just had the exact same issue, see my recent posts in this thread.

In THX mode my G10 does 2.08 gamma (about 29 ftL) when I use the AVS HD 709 to set brightness but looks really good. I get the proper 2.2 gamma if I use the method described here but it looks too dim/lifeless:



I concluded to say the hell with 2.2 gamma. It just doesn't look right on my G10. I think with some TV's you're better off just setting brightness with a pluge pattern.

Originally Posted by LarryInRI

Using the 0.65% method to set brightness only works if the gamma of your TV is 2.22 to start with. It doesn't work in reverse. Use the pluge method.

Larry

Originally Posted by Make73

Seems that USA models Cinema-mode and THX-mode limits max power of light to something around 30ftL.
SUB-BRT anything to do with this?

I think that calculating brightness or contrast is not a good option, better is measuring with HCFR´s near black and near white tests and also visual checking grayscale ramp or pluge so there´s not clipped blacks or whites at 16-235 area.

alsavforum,

I think you should check your basic settings at first, brightness and contrast.
Seems that at least brightness is too high because your black level is 0.040ftL at cinema mode.
Also some finetuning with RGB levels could be done, I would lower B-DRV at first.
(Zoom RGB page with right mouse button Scale-->RGB--> to 80-120% so it´s easier to see)
If you measure whole grayscale 0-100 at everytime it´s easier to notice how those SM adjustments affect to whole RGB area, not just 80/30IRE.

Originally Posted by Richard Smith

< HCFR still tells me my gamma is off but whenever I adjust brightness to get it to measure 2.2 the picture just looks too dark to me so I'm not going to stress about the lower gamma.>

The only way to deal with the gamma issue in Custom is to adjust the the luminance at the various levels by adjusting percentage of all the primary colors up or down. There are spread sheets around which can calculate the correct setting.

It's time consuming but it can be done

Originally Posted by alsavforum

Thanks guys for the feedback! After being at it for several hours and after several attempts, and finally getting close to 2.0 flat Gamma, I have to agree with Meteor|WAR that the 2.2 gamma is not a desirable setting. It is my opinion that the picture in cinema mode just isn't worth the effort. Even under very dark conditions, I think the calibration I achieved in "standard" still looks superior.

I wonder if that's what Panasonic intended for these sets, the weird non- exponential gamma on all modes except Cinema? It seems they want to vary the gamma as a function of light level. Maybe that's how they achieve the contrast ratios they brag about. Has anyone seen spec's for these TV's broken down into picture modes (especially contrast ratio)?

[snip]

Originally Posted by LarryInRI

The "weird" gamma in Standard is not weird at all. The Standard mode is intended for those who want 'pop' in their picture at the expense of the accuracy achieved by adhering to the industry standard. Bring an engineer, you should read Poynton. In particular:

http://www.poynton.com/notes/colour_.../GammaFAQ.html

and

http://www.poynton.com/notes/PU-PR-I...n-PU-PR-IS.pdf

Larry

Originally Posted by LarryInRI

alsavforum,

The gamma issue is one of constant discussion in the calibration forum. Although there is no agreement on the value of gamma, there is agreement that that curve should be flat. The Standard gamma is not flat. The Cinema gamma is.

Gamma is a measure of a transfer function.

Larry

Originally Posted by alsavforum

no argument here Larry- but I just can't see watching a washed out dull picture (on my tv anyway) just so I can say it's "flat". I guess, and this has already been said, it boils down to a matter of preference. That's why there's picture, brightness, and various modes in the first place, I guess.

Originally Posted by LarryInRI

Right. One person's 'washed out dull picture' is another person's very accurate picture.

Larry

Originally Posted by LarryInRI

alsavforum,

For the Panasonic TVs, the overwhelming difference in the Picture modes is gamma. Some of the more expensive Panasonic models have a gamma control that is accessible through the user menu -- but even with these sets, it is my understanding that this control is available only for specific Picture modes.

I don't know why you would have to 'recalibrate' in the Custom mode since the color temperature is global for all Picture modes. Unless, of course, you mean adjust the user menu when you use the word 'recalibrate.'

I don't know much about other flat panel brands so I can't comment on them.

Larry

Originally Posted by alsavforum

Yes- right...I guess all I'll have to do is tweak the "user" settings. I'll check it out ! BUt a question...Were the gamma plots you provided earlier are from a calibrated flat gamma- with simply the user modes being switched to "standard" and to "Custom" ? Do you know if the brightness/picture settings were also tweeked from mode to mode, or were they set to a default and / or fixed setting for the comparision?

Thanks...

Originally Posted by jackal2001

Can someone explain how to set brightness and contrast and how it directly relates to setting gamma correctly? I understand basically everything else, but this has me a little confused.

I am using a 1eye LT, HCFR software, and the AVSHD 709 DVD from this forum.

1. Brightness - Run the basic setting test pattern, so you can see 17 barely flash.

2. Contrast - What pattern do I run and what do I look for?

Now when I have these set and run the grayscale test on my TV, to achieve 2.20 gamma, I would modify my settings for brightness and contrast. This is where I get a little confused as it would take away from my origonal settings.

Originally Posted by robi1138

It's answered a few posts below but I don't believe this is how you should be setting Brightness or Contrast. If you're using THX mode, the gamma should be correct. If you're using Custom, see which setting works best but if it's not flat, nothing you do is going to change that. Set brightness by the PLUGE and leave it alone...that's my 2 cents anyway.

Also, I don't know what people are saying about 2.2 gamma not looking right...if your gamma is flat and at 2.2 (or close to it), that's what it's supposed to be...period.

Originally Posted by Meteor|WAR

jackal2001, we were recently discussing this in this thread.

Just use the pluge pattern on the AVS HD disc to set brightness and be done with it.
Use the "white clipping pattern" on the disc to set contrast (2 chapters after the black clipping pattern).

I don't know why, but adjusting brightness/contrast to achieve a 2.2 gamma reading doesn't look correct on my TV. Maybe I'm doing something wrong but so far that's the conclusion I've come to.

Originally Posted by jackal2001

I'm assuming the plunge pattern is the first pattern that states set so #17 becomes visible??? I see no reference to "plunge" in the documentation at all.

Originally Posted by jackal2001

Can someone explain how to set brightness and contrast and how it directly relates to setting gamma correctly? I understand basically everything else, but this has me a little confused.

I am using a 1eye LT, HCFR software, and the AVSHD 709 DVD from this forum.

1. Brightness - Run the basic setting test pattern, so you can see 17 barely flash.

2. Contrast - What pattern do I run and what do I look for?

Now when I have these set and run the grayscale test on my TV, to achieve 2.20 gamma, I would modify my settings for brightness and contrast. This is where I get a little confused as it would take away from my origonal settings.

Basic Settings Instructions - 10

Generally you want to have the white-level control set about as high as possible, as long as it does not introduce any detrimental effects. We will suggest starting with a high contrast setting, and then looking for any issues that might require turning down white-level. This link from Michael TLV mentions checking (1) clipping, (2) discoloration, and (3) eye-fatigue when setting white-level.

1. As long as you can see the bars marked 230-234 flash, essentially clipping is fine and you have finished with this item. If you cannot see 230- 234 flash, then you need to turn down white-level until they flash. A more conservative approach is to set white-level no higher than where most all the bars flash. It is perfectly acceptable if your display never clips near 235 and if you can always see the bars brighter than 235 flash, but the minimum is flashing from 230 to 234.

2. For discoloration, you generally want to see if you can notice any change in shade of grays near white as you adjust the white-level setting. With some displays increasing contrast beyond a point might cause the bright grayscale to begin to have a pinkish or other colored tint. If you cannot spot a change in tint by turning down contrast, then the second item is satisfied.

3. You could watch a movie to make sure whites appear relatively bright and you do not encounter eyestrain. Having eyestrain when watching would indicate a need to dim the display. If your TV seems too bright and has a backlight setting or iris control, you might try turning the setting down, which will also give you darker blacks. If the TV is still too bright after lowering those controls, then white-level could also be lowered to avoid eye-fatigue.

We mention a few white-level items in the Misc. Patterns section, and measurements can give more objective information, but generally the items mentioned above are the most straightforward issues to watch for in setting white-level. If your contrast is at a high setting where at least 230 to 234 flash, and there does not appear to be any discoloration or eye-fatigue watching, then congratulations you are done setting white-level. If you have tried to follow the above items and cannot spot any of the possible detrimental effects mentioned, and would simply like to err on the side of caution, then merely set contrast as high as it can go while you can still see that most all of the bars numbered higher than 235 flash. Some manufacturers seemingly have tried to limit the amount of possible error the white-level control can introduce, so even on the absolute highest contrast setting some digital displays may never clip levels lower than 253 and it could be difficult to clearly spot any of the items discussed.

Originally Posted by jackal2001

I did see that but I was wondering if it was the PROPER way to do it with using an eye1 lt. If you go by those settings and try to configure THX it doesn't work out too well, if at all.

Originally Posted by LarryInRI

Proper way to do what with an i1 LT? Set Contrast? If so, there is no proper way. I like 25 ftL. Above 30 ftL hurts my eyes.

I don't use a meter for setting Contrast -- just like it says in the passage I quoted above.

Larry

Originally Posted by jackal2001

I'm trying to play around with setting brightness and contrast in order to achieve a good gamma. The GUIDE doesn't specifically state how to achieve this and what to adjust for gamma. It is kind of confusing to me.

I adjust something, take a complete grayscale measurement, adjust again, over and over again.