# Samsung PNXXD8000 thread



## Robert Zohn (Aug 13, 2011)

Update..... I just received a call from Kevin Miller who calibrated a 64" D8000 a few moments ago and the color decoding is near perfect. Unlike the 59" D8000 on our shoot-out wall.

-Robert


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## Turbe (Mar 31, 2008)

*Re: Panasonic VX300 Series Q&A*

might want to get to the bottom of that sammy at your store Robert..

I also edited my post above in regards to decoding, I had combined two comments in regards to that and checking the gamut.. I really just wanted to address if there were decoding issues with the sammy, which I didn't think it had since I didn't hear anything about it from the shootout.


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## Robert Zohn (Aug 13, 2011)

*Re: Panasonic VX300 Series Q&A*

We will do that and report back. 

-Robert


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## Turbe (Mar 31, 2008)

*Re: Panasonic VX300 Series Q&A*

Hi Robert... did you get time to look into that?

You may also want to try a test going from source direct the the display.. bypassing your hdmi matrix switch.


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## janos666 (Nov 19, 2011)

*Re: Panasonic VX300 Series Q&A*



Robert Zohn said:


> I just received a call from Kevin Miller who calibrated a 64" D8000 a few moments ago and the color decoding is near perfect. Unlike the 59" D8000 on our shoot-out wall.


It's easy to get into troubles while calibrating these TVs but it's not impossible to avoid them with a well planned calibration procedure.

There are some other rules and things I used to keep myself to but the main aspects of my procedure:

- Go into the Service Menu (or preferably open the Top Debug Menu in a serial console), reset the WB calibration settings to 8x128 and recalibrate the white point by decreasing Green Gain and Blue Gain (but never increase anything above 128 and leave all the other six values at 128, do not use the offsets!).
* For the best result:
1: you need to use the Top Debug Menu, and do this WB calibration from Movie mode (instead of Dynamic in the SM) using a small 100% white window (you should use 90% if you are in the Service Menu with strictly Dynamic).
2: You should start with an ADC calibration using a special RGB test pattern (1-235 levels fed into a RGB 0-255 signal ; and you should check the debug log to see if it was successful: 4:4 and 940:940 aligned perfectly).
- Exit from the SM with a Factory Reset (or do a reset from the Top Debug Menu and close the serial console).

- Adjust Brightness and Contrast with the usual black/white clipping patterns (start with Brightness, and gently lower the Contrast if needed - depends on the Gamma).
- You won't use the 2p white balance controls in the user menu (it may sounds strange, but trust me...)
- You will use the Cool color tone (always, in every picture modes because this one has zero offsets against the SM calibration)
- Sharpness is always 0 (no need to check individually, always zero).

- Carry out the gray-scale calibration with the 10p system (using 20p small APL patterns) and the color space setup (using 92% patterns).
(Of course, you need to limit Cell Light to a level where ABL is inactive with these patterns. It's ~90 cd/m^2 for me.)

Done.

///
This procedure assumes RGB input signal (either full or limited range) but should work fine with standard YCC inputs.

I used this procedure on some D-Series Samsung PDPs (including my own) with excellent results.



I posted a more in-depth and point-to-point version of this on another forum (with a link to my custom test patterns). I just wanted to mention the main aspects to get an idea how different procedure I have when compared to the usual ISF basics (and I even go against the Samsung Service Manual in some aspects).


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## mechman (Feb 8, 2007)

*Re: Panasonic VX300 Series Q&A*

Welcome to HTS janos666! :wave:

You can pad some posts here. It can take an hour or more afterwards for your privileges to take effect. :T And then you put up a link to your custom color patterns. As for what you put up at the av sales forum, you can copy and paste it here. :huh:


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## janos666 (Nov 19, 2011)

*Re: Panasonic VX300 Series Q&A*



mechman said:


> Welcome to HTS janos666! :wave:
> 
> You can pad some posts here. It can take an hour or more afterwards for your privileges to take effect. :T And then you put up a link to your custom color patterns. As for what you put up at the av sales forum, you can copy and paste it here. :huh:


Thank you (for both the welcome and the tips). 

But as I said it in the last sentence: I didn't want to copy-paste the full stuff because this is a "VX300 Q&A" and not a "Samsung D-Series Calibration" thread. I just wanted to give an example how calibration methods can differ from each other and imply how important it is to look deep behind the scenes before you say things like "improper color decoding".


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## Robert Zohn (Aug 13, 2011)

*Re: Panasonic VX300 Series Q&A*

Looks like we may have some percent of PN59D8000s with defective color decoding. Kevin Miller just called me and posted that he just calibrated another 59" D8000 that failed the rec 709 color decoding test.

I'm planning on starting a thread on HTS with a poll for 59" D8000 owners to test the red color decoding and post their results so we can see how wide spread this issue is.

Here's a cut and paste of Kevin's post on another forum.

-Robert

_Hi All,

I did another Samsung PN59D8000 and it failed the decoder test on Red again. Color gamut was good, and luminance on red specifically was fine so it is a decoder problem.

Kevin Miller
ISF Co-instructor
TweakTV Co-Founder
Email: [email protected]
HDTV Product Development Consultant_


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## janos666 (Nov 19, 2011)

*Re: Panasonic VX300 Series Q&A*



Robert Zohn said:


> I'm planning on starting a thread on HTS with a poll for 59" D8000 owners to test the red color decoding and post their results so we can see how wide spread this issue is.


What are the exact symptoms?

I still have the opinion that it's not a color decoder bug but you simply run out of the digital ranges (you overshoot the nominal range) during the white point calibration. It happens easily and it often causes red errors because Red Gain is always the highest (the native white point of these plasma panels is very bluish and green is usually also way too much...)

This is basically a red gradient banding which may remain semi-transparent on the gray-scale (if you force the dE values low enough with the 10p controls - well, at least on the directly measured points...) but the red channel gradient is distorted at it's high levels, so it may looks like a color decoding problem.


It's not the only way, but the only fail-safe way (I know about) if you go into the Service Menu and calibrate the white point from there (starting with resetting the factory calibration back to all-128 and only lower but never increase any WB parameters - and it's safer to completely let alone the Offsets and smooth out the gray-scale with the 10p system only).



Is there a chance that you (or Kevin) may want to try out my (Samsung D-series PDP specific) calibration procedure on a unit which you (or Kevin) previously declared as faulty?
If so, then I will refine my step-to-step guide based on my latest field and home experiences and post it in your new thread.

But for the best results, you need to access the Top Debug Menu through the debug mode serial port. Are you willing to do that? (If so, then make yourself ready with a TTL-Level USB-RS232 adapter [or a Nokia CA-42 data cable] or something like that + a blank D-sub/VGA or 3.5mm Jack plug [depends on the actual model, but I think it's the Jack plug on the US D8000 TVs - I live in the EU...] and some very basic soldering equipment if you want to do it nicely - I simply cut the head of a Nokia cable and plugged the raw wires into the pins, but that's me. )

What do you say?


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## Gotchaa (Mar 23, 2011)

*Re: Panasonic VX300 Series Q&A*



Robert Zohn said:


> Looks like we may have some percent of PN59D8000s with defective color decoding. Kevin Miller just called me and posted that he just calibrated another 59" D8000 that failed the rec 709 color decoding test.
> 
> I'm planning on starting a thread on HTS with a poll for 59" D8000 owners to test the red color decoding and post their results so we can see how wide spread this issue is.
> 
> ...


Please be sure to post details of firmware/pdp version from the menu as well if possible.


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## Robert Zohn (Aug 13, 2011)

*Re: Panasonic VX300 Series Q&A*

Good idea, ^^ will do.

-Robert


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## janos666 (Nov 19, 2011)

*Re: Panasonic VX300 Series Q&A*

I am still interested what exactly you call "color decoding problem".

I measured this on my lower tier Samsung D-series PDP which is based on an MStar chipset (the D8000 uses an ARM CPU and Samsung's own video processor, but lower tier models are built around MStar chips...).

The gray lines are the CIE x,y reference coordinates of the Rec709 color space.
The continuous colored lines are the readings of the primary colors with Native color space settings.
The ragged colored lines are the readings of the primary colors with Auto color space settings (and any non-default Custom color space setup show a similar nonlinearity...).

 
 

Note that the magnitude of the problem greatly depends on the Gamma settings. I prefer gamma ~2.4, which requires Gamma = -2 which it even worse than the above +1, regarding the gamut emulation.
(But the white balance is surprisingly good if you consider that it's a default Warm2 setting without any fine-tuning: every RGB Gains/Offsets are at their defaults in both the Service and User Menus...)

Other than that, I think the color accuracy of my TV got significantly worse overall. I don't know the cause of this, but it could be one of these:
- A technician swapped my main-borad (not a long time ago) to solve a problem with remote controlling. May be I got a faulty main-board (may be with this color decoding issue...)?
- The last firmware updates for the EU models doubtfully changed the behavior of the device, so may be the color accuracy got worse with the new software...?
- May be aging of the plasma panel? (I think it would be too early, but who knows...?)

Unfortunately I didn't have either the time or the willingness to test everything in details after every changes. But I know that I would have sent this TV right back to the shop if I had the same color accuracy at the first weeks which I have now. (And chose the better contrast of the Panasonics if the colors aren't accurate on any sides...) And unfortunately I didn't make nice graphs like this, nor I archived my measurement data which I took right after the break-in to test the TV. But I tell you, it was way better than it's now.
And it's not only the internal CMS. I tried to move back to external CMS when I noticed this big change in the color accuracy. I have significantly worse dE2000 values if I evaluate an ICC profile now than I initially had in the first weeks.


Ah, sorry for the long off-off-topic. Back to the semi-off-topic D): Does the problem which you describe as "color decoding" looks like the problem I showed above (nonlinear primary channel chromaticity)?
Does your problem affect the Native or only the Auto and Custom (calibrated) color spaces?.


By the way, I sent these charts along with the raw excel spreadsheet and some additional reports (a validation report of a simple gamma+matrix ICM profile which I created for the Native color space ->like this<-).
I can't wait for their answer but I think they wouldn't even understand my problem (well, at least the first few people who take a look at it but somehow I doubt they will forward it high enough instead of treating me like an idiot until I stop emailing/calling them about this) and somehow I doubt this counts as a warranty issue, so... hahh... I bet on the wrong horse this time, I guess.


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## mechman (Feb 8, 2007)

Discussion regarding the Samsung D8000 line of displays.

Posts have been moved here from the VX300 thread to avoid confusion


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