or Connect
AVS › AVS Forum › Display Devices › Display Calibration › Plasma Owners - How do you calibrate saturation?
New Posts  All Forums:Forum Nav:

Plasma Owners - How do you calibrate saturation?

post #1 of 94
Thread Starter 
I seem to be experiencing numerous issues in trying to obtain the best saturation for my Samsung plasma model.
Ive currently resorted to using Viscas calibration disc 1% apl windows and used 50% saturation 75% luminance for my latest attempt, colours now look too bright and oversaturated.

Wondering how you guys get on and what method you use for your best results?
post #2 of 94
Use windows APL patterns, 100% saturation, and 75% luminance to start. If the results are not satisfactory try moving to 75% saturation and see if that helps make the overall gamut more accurate.
post #3 of 94
Thread Starter 
Quote:
Originally Posted by buzzard767 View Post

Use windows APL patterns, 100% saturation, and 75% luminance to start. If the results are not satisfactory try moving to 75% saturation and see if that helps make the overall gamut more accurate.

Thanks Buzzard.

Are these located on the ASHD709 disk? As i only see large or small coloured APL, full fields and windows under HCFR.
post #4 of 94
Quote:
Originally Posted by buzzard767 View Post

Use windows APL patterns, 100% saturation, and 75% luminance to start. If the results are not satisfactory try moving to 75% saturation and see if that helps make the overall gamut more accurate.

are you referencing ChromaPure?
post #5 of 94
Quote:
Originally Posted by PlasmaPZ80U View Post

are you referencing ChromaPure?

Yes - didn't stop to think that not all programs are capable.
post #6 of 94
I'm using 75% saturation 100% luminance with a BT.1886 gamma formula in CalMAN 5 using a radiance as a source.
post #7 of 94
Best 75/75 with GCD - Gamut Calibration Disk!
post #8 of 94
Thread Starter 
Be interested in seeing your saturation CIE graphs, mine doesnt line up at all.
I'll try the GCD to see if that helps.
post #9 of 94
Quote:
Originally Posted by ndaa75 View Post

Be interested in seeing your saturation CIE graphs, mine doesnt line up at all.
I'll try the GCD to see if that helps.

75% works well for me too. Tracking chart using the GCD disk can be found int the 2nd post in the Samsung D7000 & D8000 Settings/Calibration Thread
post #10 of 94
Thread Starter 
Quote:
Originally Posted by zoyd View Post

75% works well for me too. Tracking chart using the GCD disk can be found int the 2nd post in the Samsung D7000 & D8000 Settings/Calibration Thread

Perhaps its HCFR (probably me!) but im having an absolute nightmare with the samsung CMS, i dont know whats good and what isnt. I can set the Gamut using primary and secondary colours to a virtually perfect CIE chart, however when it comes to saturation its all the place. Cannot hit the reference points at all, for example im having to increase RED in the colour space all the way to 100 to hit the 75% reference saturation point, then as a result my delta luma goes crazy. Not sure what I can do here apart from select 'AUTO'.
post #11 of 94
Quote:
Originally Posted by ndaa75 View Post

... however when it comes to saturation its all the place. Cannot hit the reference points at all, for example im having to increase RED in the colour space all the way to 100 to hit the 75% reference saturation point, then as a result my delta luma goes crazy. Not sure what I can do here apart from select 'AUTO'.

In an RGB CMS like samsung has you adjust saturation by adding/subtracting the other two primaries. So to desaturate red, add equal amounts of green and blue. If you need to increase saturation of red and the green/blue sliders are already at zero, there is nothing else you can do. Which model do you have?Also, can you upload your chc file with saturation sweeps?
post #12 of 94
Thread Starter 
Quote:
Originally Posted by zoyd View Post
In an RGB CMS like samsung has you adjust saturation by adding/subtracting the other two primaries. So to desaturate red, add equal amounts of green and blue. If you need to increase saturation of red and the green/blue sliders are already at zero, there is nothing else you can do. Which model do you have?Also, can you upload your chc file with saturation sweeps?
Hi Zoyd

You are very helpful and patient - especially with a newb like me!

My model is the PS50C6500, Euro version. It has a full CMS.

OK, not sure what the CHC file is?? But anyway, take a look at the attached HCFR zipped fiiles.

The process that i adopt is to set the primary and secondary colours then take saturation readings.

I know for plasmas you shouldnt use full fields but i thre it in there anyway!
All readings taken were at 100% luminance.

 

HCFR 31st May Saturation full fields AVSHD709.zip 4.6142578125k . file

 

HCFR 31st May Saturation GCD 1% windows.zip 4.603515625k . file

 

HCFR 31st May Saturation GCD 10% windows.zip 4.603515625k . file

 

HCFR 31st May Saturation Windows AVSHD709.zip 4.611328125k . file
post #13 of 94
Quote:
Originally Posted by ndaa75 View Post

I seem to be experiencing numerous issues in trying to obtain the best saturation for my Samsung plasma model.
Ive currently resorted to using Viscas calibration disc 1% apl windows and used 50% saturation 75% luminance for my latest attempt, colours now look too bright and oversaturated.

Wondering how you guys get on and what method you use for your best results?

Hi ndaa75,

The best way to set Color/Saturation on any display with a Blue Only feature like the Samsungs is to use SMPTE Color Bars (75%), separate Blue and adjust according to the panel. Typically I set Samsungs at either 46 or 47 for Color and it looks correct. Try that.
post #14 of 94
Thread Starter 
Quote:
Originally Posted by Monitorman View Post

Hi ndaa75,

The best way to set Color/Saturation on any display with a Blue Only feature like the Samsungs is to use SMPTE Color Bars (75%), separate Blue and adjust according to the panel. Typically I set Samsungs at either 46 or 47 for Color and it looks correct. Try that.

Thanks Monitorman.

So you are suggesting that i do not use a meter at all, just use the blue filter?
post #15 of 94
Quote:
Originally Posted by ndaa75 View Post

Hi Zoyd

You are very helpful and patient - especially with a newb like me!

My model is the PS50C6500, Euro version. It has a full CMS.

OK, not sure what the CHC file is?? But anyway, take a look at the attached HCFR zipped fiiles.

The process that i adopt is to set the primary and secondary colours then take saturation readings.

I know for plasmas you shouldnt use full fields but i thre it in there anyway!
All readings taken were at 100% luminance.

Your GCD APL run has very typical results and I don't think you'll gain anything by further tweaking. You can probably improve the undersaturated red at 75% a little bit by decreasing blue (the comments say the CMS setting is R:44 G:0 B:6) but this would not really be noticeable and your red saturation at 25% and 50% is good where flesh tones reside.
post #16 of 94
The blue filter method is a waste of time if you are using a meter on a video display with full CMS controls. Set the color and tint to their middle/default settings and leave them there.

Use window patterns that cover 10%-18% of the screen area for a plasma panel. If the window patterns are too large or too small you will have a bad calibration result.

Use 75% color patterns which are close to 50% stimulus when your Gamma is 2.2-2.3... that means if 100% red measures 7 fL for luminance, the 75% red window pattern will measure about 3.5 fL. The luminance measurement for 75% windows will vary somewhat depending on what Gamma you have set the video display to. I would recommend a gamma of 2.25-2.3 for your plasma model.

Your calibration software should have some means of showing you hue, saturation, and luminance for each color when you are doing color calibration. Many programs show you a triangle that represents HDTV color space (Rec. 709). If a color measures INSIDE the triangle, it is under-saturated. If a color measures outside the triangle, it is over-saturated. One of the CMS controls in the Samsung displays will move the measured color between over- and under-saturation. The calibration software has to tell you when you have selected the correct saturation, sometimes this is done by minimizing the dE error, some software shows you a "box" that represents where the color should measure and your are correct when the measurement "dot" is in the center of the small box. If you don't know how this works in your calibration software, you need to find out more information about your calibration software.

Some CMS controls will interact... sometimes a lot, sometimes a little. So it's not unusual for one adjustment to require a tweak on one of the other 2 adjustments (3 adjustments total for each primary and complimentary color, 18 controls total).
post #17 of 94
Thread Starter 
Quote:
Originally Posted by Doug Blackburn View Post

The blue filter method is a waste of time if you are using a meter on a video display with full CMS controls. Set the color and tint to their middle/default settings and leave them there.

Use window patterns that cover 10%-18% of the screen area for a plasma panel. If the window patterns are too large or too small you will have a bad calibration result.

Use 75% color patterns which are close to 50% stimulus when your Gamma is 2.2-2.3... that means if 100% red measures 7 fL for luminance, the 75% red window pattern will measure about 3.5 fL. The luminance measurement for 75% windows will vary somewhat depending on what Gamma you have set the video display to. I would recommend a gamma of 2.25-2.3 for your plasma model.

Your calibration software should have some means of showing you hue, saturation, and luminance for each color when you are doing color calibration. Many programs show you a triangle that represents HDTV color space (Rec. 709). If a color measures INSIDE the triangle, it is under-saturated. If a color measures outside the triangle, it is over-saturated. One of the CMS controls in the Samsung displays will move the measured color between over- and under-saturation. The calibration software has to tell you when you have selected the correct saturation, sometimes this is done by minimizing the dE error, some software shows you a "box" that represents where the color should measure and your are correct when the measurement "dot" is in the center of the small box. If you don't know how this works in your calibration software, you need to find out more information about your calibration software.

Some CMS controls will interact... sometimes a lot, sometimes a little. So it's not unusual for one adjustment to require a tweak on one of the other 2 adjustments (3 adjustments total for each primary and complimentary color, 18 controls total).

OK thanks for this Doug.

I get most of what youre saying, however the problem occurs when I have to set saturation. For example, if im trying to set the colour RED correctly im generally having to increase the red slider in order to increase the saturation level to the target point, however the consequence of doing so increases the luminance. Not sure how to get past this.
post #18 of 94
Quote:
Originally Posted by ndaa75 View Post

OK thanks for this Doug.

I get most of what youre saying, however the problem occurs when I have to set saturation. For example, if im trying to set the colour RED correctly im generally having to increase the red slider in order to increase the saturation level to the target point, however the consequence of doing so increases the luminance. Not sure how to get past this.

I explained this already in post #11, the red slider for the red primary controls luminance not saturation of red. If you have blue and green set to 0 for that primary, that is the maximum saturation you can get. Trying to increase luminance to increase saturation will not work, as you have already noted.
post #19 of 94
Thread Starter 
Quote:
Originally Posted by zoyd View Post

I explained this already in post #11, the red slider for the red primary controls luminance not saturation of red. If you have blue and green set to 0 for that primary, that is the maximum saturation you can get. Trying to increase luminance to increase saturation will not work, as you have already noted.

Yes, thanks i see now - is there any service menu tweak that can help?
post #20 of 94
Quote:
Originally Posted by ndaa75 View Post

Yes, thanks i see now - is there any service menu tweak that can help?

no, the maximum saturation is determined by the narrowness of the spectral distribution of the phosphors and that can't be adjusted. As I said earlier the calibration results you have in the GCD file (25% APL w/1% windows) looks very good, be happy.
post #21 of 94
Quote:
Originally Posted by ndaa75 View Post

Yes, thanks i see now - is there any service menu tweak that can help?

only different firmware Samsung can fix it or videoprocessor!
post #22 of 94
Are you measuring window test patterns in a dark room? Ambient light will reduce measured saturation. Full field test patterns will ruin luminance readings on a plasma.

I have not found Samsung plasmas to have undersaturated reds and greens in the Custom color space, Movie mode. So long as green and blue are at zero (for red) and red and blue are at zero (green), these primaries should be pretty close to the ideal.

If you measure something significantly different, then you have a non-standard display, your meter is not measuring accurately, or you are measuring under non-optimal conditions.
post #23 of 94
Quote:
Originally Posted by TomHuffman View Post

I have not found Samsung plasmas to have undersaturated reds and greens in the Custom color space, Movie mode. So long as green and blue are at zero (for red) and red and blue are at zero (green), these primaries should be pretty close to the ideal.

He is finding the same thing, at 100% saturation everything is fine. It's at 75% saturation he is finding that red x is low. The CMS tracking is off, not the native primary saturation. deltax (measurement-target)=-0.025

btw - it's the same on my display, if you nail 100%, 75% is undersaturated while 25% and 50% are oversaturated (but not by much).
post #24 of 94
Thread Starter 
Quote:
Originally Posted by TomHuffman View Post

Are you measuring window test patterns in a dark room? Ambient light will reduce measured saturation. Full field test patterns will ruin luminance readings on a plasma.

I have not found Samsung plasmas to have undersaturated reds and greens in the Custom color space, Movie mode. So long as green and blue are at zero (for red) and red and blue are at zero (green), these primaries should be pretty close to the ideal.

If you measure something significantly different, then you have a non-standard display, your meter is not measuring accurately, or you are measuring under non-optimal conditions.

Hi Tom

Thanks for your input.

I'll give you an example of what im experiencing.

If i load up on AVSHD disk the HCFR window colour pattern for red at 75% amp and 100% saturation or the 100% red saturation window i have 4-5% green and a 5% negative blue (im referring to the RGB colour bars). I adjust the blue to reach 0% but cannot reduce green any further as the slider is at 0.

If i load up large APL (red 75% amp, 100% saturation) or full field red 100% saturation window then green is reduced to 1% with a smaller negative blue.

Window vs APL or full fields are giving different results for the same amp/sat.

Yes, im also doing this in a darkened room.
post #25 of 94
Сhange color in TV give me something?
Saturation and brightness colors can be changed is not the same when you change colors and CMS?
post #26 of 94
Quote:
Originally Posted by ndaa75 View Post

OK thanks for this Doug.

I get most of what youre saying, however the problem occurs when I have to set saturation. For example, if im trying to set the colour RED correctly im generally having to increase the red slider in order to increase the saturation level to the target point, however the consequence of doing so increases the luminance. Not sure how to get past this.

As I said in the original post, sometimes moving one control causes some other parameter to change. So you have to adjust another control (or all 3) every time you make one adjustment. You have 3 primary colors, red, green, and blue and 3 complimentary colors... magenta, cyan, and yellow. Each color has 3 controls (at least I've never seen a Samsung display with CMS and less than 3 controls per color). Those controls control hue (the color), the saturation (what you are trying to change), and luminance (how bright the color is). Sort of... as mentioned, those 3 controls may interact. So if you adjust saturation and luminance goes up, you have to adjust the luminance control lower to keep the color from getting too bright. When adjusting red, the hue control will likely move the measured red point closer to green when you move it in one direction or towards blue when you move the control in the other direction. The saturation control... sounds like you know what that does. The Luminance control will move the brightness of the color in question up or down.

So... let's say you adjust the saturation control to get red closer to the Rec709/HDTV coordinates for red, but red gets brighter while the saturation improves. You then lower the luminance control to get red brightness correct again. But that causes red to de-saturate again. So you make another move with the saturation control and again, you improve saturation, but red is too bright again. So you use the luminance control to make it dimmer, but that, again, de-saturates red. You are stuck in this cycle and can't get the saturation and luminance correct at the same time. This is where the "art" of calibration comes into play. Your TV is simply not capable of making the red point accurate. So you have to decide whether the saturation error or the luminance error is more obvious and live with one or the other. Another option is to leave half the error in saturation and half the error in luminance and live with that... I'd probably do the latter.

The other thing about errors, luminance errors in particular, tend to be more problematic if there are large swings in luminance errors... say red, green, and magenta are too bright while cyan, blue, and yellow are too dim... that's a bad scenario for image quality. You want them all within 10%-15% of each other (less if possible). So if you end up with red being too bright and there's nothing you can do about it, you should make all the other colors too bright also... not by a crazy amount, but you definitely don't want a situation where red is 30% too bright and some other color is 30% too dim. If I had a problem where red was going to have to be 30% too bright, I'd probably try to get the other colors to be about 15% too bright.

Using the Color control in the user menu MIGHT help with red saturation---or not. You won't know until you adjust it and re-measure and see if increasing Color allows you to get closer to the ideal red point while maintaining a more accurate luminance level. Color controls do different things in different displays so you'll want to measure ALL the colors after an adjustment of the Color control because the Color control might help you fix one problem, but it could create a problem with some other color. Our vision is most sensitive to Green so you want green to be as accurate as you can make it. Cyan and Yellow should be the next most accurate colors. Red and magenta should be next in line for accuracy, and blue errors would be the least-obvious errors. But large errors in any color will be visible so you have to keep things in balance (again, part of the "art" of calibration that you can't learn in descriptions of how to calibrate).
post #27 of 94
Thread Starter 
Quote:
Originally Posted by Doug Blackburn View Post

As I said in the original post, sometimes moving one control causes some other parameter to change. So you have to adjust another control (or all 3) every time you make one adjustment. You have 3 primary colors, red, green, and blue and 3 complimentary colors... magenta, cyan, and yellow. Each color has 3 controls (at least I've never seen a Samsung display with CMS and less than 3 controls per color). Those controls control hue (the color), the saturation (what you are trying to change), and luminance (how bright the color is). Sort of... as mentioned, those 3 controls may interact. So if you adjust saturation and luminance goes up, you have to adjust the luminance control lower to keep the color from getting too bright. When adjusting red, the hue control will likely move the measured red point closer to green when you move it in one direction or towards blue when you move the control in the other direction. The saturation control... sounds like you know what that does. The Luminance control will move the brightness of the color in question up or down.

So... let's say you adjust the saturation control to get red closer to the Rec709/HDTV coordinates for red, but red gets brighter while the saturation improves. You then lower the luminance control to get red brightness correct again. But that causes red to de-saturate again. So you make another move with the saturation control and again, you improve saturation, but red is too bright again. So you use the luminance control to make it dimmer, but that, again, de-saturates red. You are stuck in this cycle and can't get the saturation and luminance correct at the same time. This is where the "art" of calibration comes into play. Your TV is simply not capable of making the red point accurate. So you have to decide whether the saturation error or the luminance error is more obvious and live with one or the other. Another option is to leave half the error in saturation and half the error in luminance and live with that... I'd probably do the latter.

The other thing about errors, luminance errors in particular, tend to be more problematic if there are large swings in luminance errors... say red, green, and magenta are too bright while cyan, blue, and yellow are too dim... that's a bad scenario for image quality. You want them all within 10%-15% of each other (less if possible). So if you end up with red being too bright and there's nothing you can do about it, you should make all the other colors too bright also... not by a crazy amount, but you definitely don't want a situation where red is 30% too bright and some other color is 30% too dim. If I had a problem where red was going to have to be 30% too bright, I'd probably try to get the other colors to be about 15% too bright.

Using the Color control in the user menu MIGHT help with red saturation---or not. You won't know until you adjust it and re-measure and see if increasing Color allows you to get closer to the ideal red point while maintaining a more accurate luminance level. Color controls do different things in different displays so you'll want to measure ALL the colors after an adjustment of the Color control because the Color control might help you fix one problem, but it could create a problem with some other color. Our vision is most sensitive to Green so you want green to be as accurate as you can make it. Cyan and Yellow should be the next most accurate colors. Red and magenta should be next in line for accuracy, and blue errors would be the least-obvious errors. But large errors in any color will be visible so you have to keep things in balance (again, part of the "art" of calibration that you can't learn in descriptions of how to calibrate).

Thank you Doug for a very comprehensive explanation.
Is this a common issue for plasma units?
Also, I've read many about many different colour fields to use for calibration - some say use large APL patters or small APL patters (such as those on the AVSHD709 disk), others say the standard window format is fine.
What is the general recommendation here for colour calibration on plasma TV's?
post #28 of 94
Hi Doug.

I have a problem with this topic. I have a JVC X-30 and calibrate I encountered this problem.

For calibration and use Radiance Mini 3D, chromapure with D3 PRO Certificate.

I tested with two different colorimeters D3 PRO certificates. One of them is new. The colorimeters is perfect conditions.


BEFORE

SETTINGS: 6500K, RESPONSE GAMMA NORMAL, GAMUT STANDAR:



AFTER:




To correct the red light used by the control decoder red glare mini-3D, but if you increase the red decoder to correct the brightness, red trim levels > 235 in the color test pattern cut AVSHD. That is the precise point at which I can get without clipping levels. If continuous red increasing control to further reduce the error in the red light, crushing occurs levels below 235.

The blue light has been compensated properly interact with saturation and hue

And if I use the reference white mini CMS 3D to compensate for the brightness of primary , lose maximum brightness at 100% white and equally crushing occurs color clipping levels

There are also problems of saturation in green and cyan. I know that CMS can not add saturation, so I understand that I must live with it That complicated Jvc X-30!

You think you can improve these results?. I can do something to improve them?


Excuse my english

Thank you
post #29 of 94
Quote:
Originally Posted by ndaa75 View Post

OK thanks for this Doug.

I get most of what youre saying, however the problem occurs when I have to set saturation. For example, if im trying to set the colour RED correctly im generally having to increase the red slider in order to increase the saturation level to the target point, however the consequence of doing so increases the luminance. Not sure how to get past this.

Hi All,

Luminance of the colors is more important than the actual x and y coordinate of the color especially if it is too low. Beware of Samsung CMS as sometimes it causes red and green luminance to be much too high. If that happens it is better not to use it at all.

Bringing color down to 46 or 47 where it belongs will also reduce the luminance of all of the primaries somewhat and that usually is a good thing. Color at 50 on any Samsung made in the last 3 to 4 years is simply too high and will result in over saturated skin tones and colors. If you use the Blue only feature in the Advanced Menu with SMPTE color bars this will be quite clear. I have never seen a Samsung with Luminance Control in the CMS. It is simply Red, Green and Blue. I wish it did have a Luminance control for each color A.K.A. the Panasonics. Then it would a useful feature. As it is it is flawed.
post #30 of 94
Quote:
Originally Posted by Monitorman View Post

Hi All,

I have never seen a Samsung with Luminance Control in the CMS. It is simply Red, Green and Blue.

This has not been my experience (nor others) for D8000-series samsung plasmas. The decoder is nearly perfect (49-50 depending on color) via blue, red, or green only mode. Yes, luminance is too high once you hit the DSP in auto or native, but the custom CMS works perfectly to correct it. The controls work like this (red primary as example):

1. Luminance: +/- R
2. Hue: +/- G and B in unequal amounts
3. Saturation +/- G and B in equal amounts

For secondaries I'll use yellow as an example:

1. Luminance: +/- G,R in equal amounts
2. Hue: +/- G,R in unequal amounts
3. Saturation: +/- B



R for red usually ends up around 40.
Blue and Green are not as bad and end up between 40-50 while green hue always gets pulled toward red, typically 15-20 clicks.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Display Calibration
AVS › AVS Forum › Display Devices › Display Calibration › Plasma Owners - How do you calibrate saturation?