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Basic Guide to Color Calibration using a CMS (updated and enhanced) - Page 57

post #1681 of 1810
11/23/10 at 3:17pm
Hey Tom,

Just started reading this thread from the start a few hours ago and holy cow that's a lot of serious technical information right there. I don't presume to understand half of it yet, but hopefully with some practical application it will become clearer.

Thing is, I don't have a colorimeter of any kind. Do you know of anything under £100 (not sure what that is in dollars, somewhere around 130 maybe?) that is anywhere near accurate enough to do a half decent job? I was originally looking at the SpyderTV but heard that they can be poorly calibrated out of the box and I don't know anyone with more accurate equipment that I can use to calibrate it. Not that I know yet what any of that really means.

I recently bought a Samsung UE32C4000 LED Edge-Lit LCD, and I've been having a few issues getting a decent picture using just DVE and some White Balance settings I found on the internet. From what I've read on here am I right in thinking that those controls (RGB offset and RGB Gain, 6 controls total) would be changing the colour saturation but also the colour intensity, thus adversely affecting the general picture quality even if the saturation is correct? So, unless I'm willing to go into the service menus (which may not even contain full colour controls anyway and will void my warranty I think) would you advise leaving White Balance settings on factory defaults?

Apologies for all the questions, I hope it's not presumptuous or pushy of me (especially as I have another thread vaguely concerning this in a different part of the forum but nobody has responded to it as far as I'm aware). I'm just a little frustrated, especially as I'm very satisfied with the picture on my tiny little Samsung LE19R36, but also very interested in learning how to better calibrate a display generally.

Thanks in advance for any advice, and sorry in advance if I am indeed being too pushy with my line of questioning.

Paul.
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post #1682 of 1810
11/23/10 at 6:31pm
Thread Starter 
http://www.amazon.co.uk/Pantone-EODL...0565850&sr=8-2

Quote:
Originally Posted by LordOfThundera View Post

Hey Tom,

Just started reading this thread from the start a few hours ago and holy cow that's a lot of serious technical information right there. I don't presume to understand half of it yet, but hopefully with some practical application it will become clearer.

Thing is, I don't have a colorimeter of any kind. Do you know of anything under £100 (not sure what that is in dollars, somewhere around 130 maybe?) that is anywhere near accurate enough to do a half decent job? I was originally looking at the SpyderTV but heard that they can be poorly calibrated out of the box and I don't know anyone with more accurate equipment that I can use to calibrate it. Not that I know yet what any of that really means.

I recently bought a Samsung UE32C4000 LED Edge-Lit LCD, and I've been having a few issues getting a decent picture using just DVE and some White Balance settings I found on the internet. From what I've read on here am I right in thinking that those controls (RGB offset and RGB Gain, 6 controls total) would be changing the colour saturation but also the colour intensity, thus adversely affecting the general picture quality even if the saturation is correct? So, unless I'm willing to go into the service menus (which may not even contain full colour controls anyway and will void my warranty I think) would you advise leaving White Balance settings on factory defaults?

Apologies for all the questions, I hope it's not presumptuous or pushy of me (especially as I have another thread vaguely concerning this in a different part of the forum but nobody has responded to it as far as I'm aware). I'm just a little frustrated, especially as I'm very satisfied with the picture on my tiny little Samsung LE19R36, but also very interested in learning how to better calibrate a display generally.

Thanks in advance for any advice, and sorry in advance if I am indeed being too pushy with my line of questioning.

Paul.
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post #1683 of 1810
11/24/10 at 4:55am
Been a while since I have done this but let me see if I can shed a little light on the subject for you as simple as possible.. Whatever you do without a meter is going to be pointless and most likely make things worse for you. Especially if you start getting into the Offsets and Gains...

RGB Offset adjusts red green and blue individually from medium gray down to black.

RGB Gain adjusts the red green and blue individually from a medium gray up to white...

a perfect gray scale from black to white will have no tint of color to it at all. for example to much Red gain and your whites will start looking pinkish.

The eye one display LT that Tom suggested is the one and only meter to get if you don't want to spend a lot of money. It will give you respectable results and hours of fun learning. My only question about the LT is, Will it work with a new LED TV? Tom can probably answer that for sure. I guess it depends on the software you are using if it has a look up chart for that particular meter..

Try looking up your TV model number here and see if anybody has some calibrated settings you could try. Every unit is different but it may get you closer than you are getting by eye.
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post #1684 of 1810
11/24/10 at 10:01am
Thread Starter 
Quote:
Originally Posted by dpnaylor View Post
My only question about the LT is, Will it work with a new LED TV?
There's nothing special about LED backlighting that poses special problems for colorimeters.
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post #1685 of 1810
11/24/10 at 12:40pm
Hey guys,

I've decided to take it back and get the LE32C530 instead, as it seems to be a pretty decent set from what I've seen on here (and I'm on my second set with build quality issues in a row, missing screws etc.). Either of you guys have experience with it? Even though it's only about £20 cheaper I'd rather have a set that's been tried and tested (knowledge about the UE32C4000 seems practically non-existent). Unless you guys would recommend something else in that price range of course (sorry, wrong thread for that I know, but nobody over in the recommendations thread seems interested).

I'll definitely be picking up the Eye One though, and working through the tutorial on here.
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post #1686 of 1810
12/17/10 at 1:55pm
I see that the Samsung PNxxB650 is listed, within the first post, as a plasma with CMS. I have the Insignia NS-P501Q-10A, which is supposed to be the same as the Samsung PNxxB650. I have not dug too far into the service menu, but I was wondering if anyone knows if there is a CMS within the service menu.
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post #1687 of 1810
12/17/10 at 5:43pm
Isn't the insignia a 720p display?
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post #1688 of 1810
12/17/10 at 6:51pm
Quote:
Originally Posted by angryht View Post
I see that the Samsung PNxxB650 is listed, within the first post, as a plasma with CMS. I have the Insignia NS-P501Q-10A, which is supposed to be the same as the Samsung PNxxB650. I have not dug too far into the service menu, but I was wondering if anyone knows if there is a CMS within the service menu.
I don't think it is the same as the Samsung B650. Anyway, the CMS in the Samsung is only in the user menu (advanced picture settings, custom color space).
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post #1689 of 1810
12/17/10 at 7:53pm
http://www.spectracal.com/documents/...2010-12-06.pdf

Is a very good document on what controls to adjust and in what direction to fit the CIE charts! Note Page 26.
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post #1690 of 1810
12/17/10 at 8:44pm
Quote:
Originally Posted by PlasmaPZ80U View Post
I don't think it is the same as the Samsung B650. Anyway, the CMS in the Samsung is only in the user menu (advanced picture settings, custom color space).
You're right. I guess it's a PN50B430P2D. Never mind. I saw that the service menu said: "adjustments and controls are identical to Samsung PNxxB650" That must just be for the grayscale.
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post #1691 of 1810
1/2/11 at 4:07pm
Tom et al, do you have any experience with the CMS implementations in some of the newer LG or Sharp flat panels? I've been looking at their manuals seeing what calibration capabilities that they had since I may be in the market for a new flat panel. I'm wondering if their CMS implementations are as good as the Samsung's.


--tom
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post #1692 of 1810
1/2/11 at 8:24pm
Quote:
Originally Posted by thomasl View Post

Tom et al, do you have any experience with the CMS implementations in some of the newer LG or Sharp flat panels? I've been looking at their manuals seeing what calibration capabilities that they had since I may be in the market for a new flat panel. I'm wondering if their CMS implementations are as good as the Samsung's.


--tom

Some of the reviews on the high end LG models seem to show that in THX mode at least they are already pretty spot-on.
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post #1693 of 1810
1/3/11 at 11:35am
Quote:
Originally Posted by thomasl View Post
Tom et al, do you have any experience with the CMS implementations in some of the newer LG or Sharp flat panels? I've been looking at their manuals seeing what calibration capabilities that they had since I may be in the market for a new flat panel. I'm wondering if their CMS implementations are as good as the Samsung's.


--tom
We own a LG that I bought back in June 2010 and we also bought a LG for our son about a month earlier so I spent some time calibrating them. See here for what I discovered about the CMS:
http://www.avsforum.com/avs-vb/showt...013&highlight=
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post #1694 of 1810
1/27/11 at 11:46am
Hey Tom. I apologize in advance as I am sure this has been answered in this thread. But my search turned up squat.

On your calibration DVD, what size are the windows? I am in need of windows smaller than AVS/Getgray/DVE. AVS does have the small APL, but that actually makes voltage clamp down in the mid-range.
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post #1695 of 1810
1/27/11 at 5:14pm
Thread Starter 
Quote:
Originally Posted by Nutdotnet View Post

Hey Tom. I apologize in advance as I am sure this has been answered in this thread. But my search turned up squat.

On your calibration DVD, what size are the windows? I am in need of windows smaller than AVS/Getgray/DVE. AVS does have the small APL, but that actually makes voltage clamp down in the mid-range.

About 13%.
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post #1696 of 1810
1/28/11 at 6:26am
Good info
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post #1697 of 1810
1/30/11 at 6:33am
Quote:


Setting White Level (Contrast)

The Contrast control determines the peak output your display will provide. Set too low you lose image punch and lower contrast ratios. Set this too high and you lose color accuracy and detail in bright scenes and you may suffer from eye strain.

The standard method for setting Contrast requires that you look at a test pattern that has a just-below-white stripe against a white background. You are supposed to set Contrast as high as you can without losing the ability to distinguish the just-below-white stripe from full white. I included such a pattern on the calibration DVD.

However, there are a couple of problems with this method.

Some displays, especially LCDs, will never suffer from loss of high level detail even with Contrast set to 100%. This method will recommend a setting that is much too high.
This method does not take into consideration color performance. Many displays will lose their ability to track a neutral white at high output levels with Contrast set as high as this method recommends.

Thus, I think that a better method for setting Contrast is to just set it at a level consistent with good color performance and reasonable light output for a given display device. What's a reasonable level?

CRT tubes: 30-40 fL
Plasma: 30-40 fL
LCD flat panel: 30-50 fL
Digital rear projection: 30-40 fL
Digital front projection: 12-16 fL

Tom, most/all LCD's and many plasmas also have Cell Light or Back light controls embedded. How do these factor into the setting of White Level as they also impact the measured fL. I.e., one can likely get to a fL of 40fL on an LCD with a contrast setting of say 70 and a backlight of 20, and at the same time a contrast setting of 100 and a backlight setting of under 10.

Would one simply pump contrast up as high as possible (keeping in mind the WTW pattern) and then drop back light until you reach the desired fL?
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post #1698 of 1810
1/30/11 at 10:19am
Thread Starter 
Quote:
Originally Posted by pbc View Post

Tom, most/all LCD's and many plasmas also have Cell Light or Back light controls embedded. How do these factor into the setting of White Level as they also impact the measured fL. I.e., one can likely get to a fL of 40fL on an LCD with a contrast setting of say 70 and a backlight of 20, and at the same time a contrast setting of 100 and a backlight setting of under 10.

Would one simply pump contrast up as high as possible (keeping in mind the WTW pattern) and then drop back light until you reach the desired fL?

They work together. The biggest difference is that raising the backlight will also raise the black level. The rule of thumb is to use the lowest backlighting you can to get adequate light output.
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post #1699 of 1810
1/30/11 at 8:20pm
Thanks for the post. I'm sure it will come in handy. Wish I had seen something like this sooner.
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post #1700 of 1810
3/31/11 at 11:32am
So I'm about to jump in and calibrate my first projector, well actually my first of anything. So I purchased an eyeone LT and I am planning on using the HCFR software. The projector that I will be playing with is a Mits HC4000 (which I believe to be very close to the HC3800), so I need to do some more reading using your original post and planning to use that in combination with the claibration for dummies guide with the Blu Ray DVE disc..So what I was wondering is my goals is to try to have some presets for watching movies, HDTV(ambient light) and maybe a sports setting. Any suggestions or recomendations on best approach to achieve this, should I use a cooler temp like 7500 for Sports which would probably allow me to be a little brighter? Any thoughts/guidance would be appreciated...Thanks.
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post #1701 of 1810
3/31/11 at 12:37pm
I have an older Mits the HD1000U. That has 3 presets to it. I calibrated one of them then all I did was adjust the brightness, contrast and brilliant color for the last two presets.. Bumping each of those up a bit for the second preset then a bit more for the last preset. preset two for gaming really then preset three had the highest settings for sports. I found I could bump the brightness almost all the way up for sports. The Contrast you cant go to crazy with or the Whites really get washed out.
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post #1702 of 1810
3/31/11 at 1:31pm
Quote:
Originally Posted by dpnaylor View Post

I have an older Mits the HD1000U. That has 3 presets to it. I calibrated one of them then all I did was adjust the brightness, contrast and brilliant color for the last two presets.. Bumping each of those up a bit for the second preset then a bit more for the last preset. preset two for gaming really then preset three had the highest settings for sports. I found I could bump the brightness almost all the way up for sports. The Contrast you cant go to crazy with or the Whites really get washed out.

Sounds good, when you bump the brightness does it force you to go back and re-adjust anything else?
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post #1703 of 1810
3/31/11 at 1:39pm
bumping the brightness and contrast some wont mess up the grey scale to much once it is already calibrated. Some projects have presets that bump the green levels to try and get more lumens but my projector is pretty bright already. I have not really had the need to go back in and adjust the grey scale again.. My projector only has grey scale adjustments anyway. I cant adjust my primaries at all..
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post #1704 of 1810
4/11/11 at 8:19am
Hi Tom,

It appears I'll be joining the ranks of your customers with ChromaPure. I am purchasing a meter and software package for a new TV I am to receive this week. This brings me to my question. I noticed at the beginning of the thread some select Samsung plasmas were listed with a full CMS. I am taking delivery of their new PN64D7000 plasma and I cannot tell whether or not it has a full 3D CMS; however, I suspect it does not. I know compared to a lot TV's it has excellent PQ controls, which was one of the reasons I chose it. For example, I know it has 10 pt white balance for greyscale, and as best I can tell from the manual it has a great deal of control over color, as well. It appears that control is over the primaries however. If it turns out the CMS is a good one, but not a full 3D CMS, what video processors would you recommend to provide such, or do you think the Samsung plasmas are close enough to avoid an independent video processor (from a value perspective)? If the video processor would result in a noticeable PQ improvement and full 3D CMS for another $1k-$2k, then I think it would be worth it. I know it's a subjective question, but I'd appreciate your opinion along with anyone else. I intend to calibrate this TV and very much want to get as close as I can to reference.

Thanks,

Tjax
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post #1705 of 1810
4/11/11 at 8:32am
It has Gamma, 2 pt., 10 pt., and full 3D CMS. The whole shebang!

VP = DVDO iScan Duo especially now that we have a new controller thanks to a forum member. http://www.avsforum.com/avs-vb/showp...8&postcount=28
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post #1706 of 1810
4/11/11 at 8:48am
Thanks for the fast response, Buzz. Long time no talk, huh? So your take is that Samsung has the whole Shebang? Glad to hear it. I had held off from pulling the trigger on CurtPalme due to their total package deals. I figured it best to sort out whether I'd need a video processor to get total control over calibration, before I bought the equipment to calibrate. After all, great equipment won't matter if I can't control the picture. You've been a lot of help in my decision process. Just when I think I'm done reading & thinking, I find there's even more. Thanks for taking the time.
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post #1707 of 1810
4/11/11 at 11:45am
Thread Starter 
Quote:
Originally Posted by tjacks84 View Post

I noticed at the beginning of the thread some select Samsung plasmas were listed with a full CMS. I am taking delivery of their new PN64D7000 plasma and I cannot tell whether or not it has a full 3D CMS; however, I suspect it does not.

It does. Any Samsung display that has a Custom Color Space option has a full 3D CMS.
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post #1708 of 1810
5/19/11 at 6:31pm
I adjusted the greyscale now I'm attempting to adjust the color using CMS on an epson 8350. I have Hue, Saturation, and Brightness controls for each color. Adjusting the Hue affects both x,y. Adjusting Saturation also affects both x,y. Due to that I can come up with the correct x,y value with a number of different Hue & Saturations settings. How do I know which setting is correct? Which one should i adjust first?
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post #1709 of 1810
5/20/11 at 5:07am
Quote:
Originally Posted by jmoakk View Post

I adjusted the greyscale now I'm attempting to adjust the color using CMS on an epson 8350. I have Hue, Saturation, and Brightness controls for each color. Adjusting the Hue affects both x,y. Adjusting Saturation also affects both x,y. Due to that I can come up with the correct x,y value with a number of different Hue & Saturations settings. How do I know which setting is correct? Which one should i adjust first?

I'm by no way an expert but I had invested quite a lot of time to adjust the CMS of my Panny 4000 to achieve fairly good result.

So, when it comes to the basic concept, adjusting Saturation is equivalent to adjusting its distance from the D65 white point; and adjusting Hue is equivalent to adjusting its swinging angle with respect to the D65 white point. I assume you know about this part (don't you?).

Therefore, THEORETICALLY speaking, for a particular primary/secondary color, there is only one Saturation/Hue/Brightness combination that can bring the color back to the correct xyY. To put it into another aspect - take 100% saturated Yellow as an example, it should be measured as 107% Red, 107% Green, and 0% Blue for the perfect alignment in the correct xy position (just ignore the Brightness (Y) part for the sake of simplicity). If your measurement comes out as 104% Red, 108% Green, and 5% Blue, that means it is both undersaturated (because it contains a little bit of Blue) and deviated towards Green a little bit (Unbalanced Red & Green). Adjusting Hue alone may allow you to get Red & Green balanced at 106% / 106%, but it is still undersaturated. So you need to increase Saturation to get the perfect RGB combination (i.e. xy coordinate) of 107% / 107% / 0%. You get it?

However, poorly implemented CMS will usually cause you much time to settle down at a correct setting because, e.g. when you adjust one aspect (e.g. Saturation) it also affects the other aspects (e.g. Hue and/or Brightness) unexpectedly.

Hope that helps.
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post #1710 of 1810
5/20/11 at 7:22am
Thread Starter 
Quote:
Originally Posted by jmoakk View Post

I adjusted the greyscale now I'm attempting to adjust the color using CMS on an epson 8350. I have Hue, Saturation, and Brightness controls for each color. Adjusting the Hue affects both x,y. Adjusting Saturation also affects both x,y. Due to that I can come up with the correct x,y value with a number of different Hue & Saturations settings. How do I know which setting is correct? Which one should i adjust first?

The correct xy coordinates for the standard gamuts are listed at the beginning of this thread. It doesn't matter which (saturation or hue) you adjust first so long as you end up with the correct coordinates when you are finished.
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