View Full Version : My first attempt, please help


hoops10
01-06-09, 08:52 PM
I used the AVS HD disc and my new I1-LT and spent a good 3 hours on it. Wow, very sensitive. I mean that when you try to adjust blue and red brightness controls for lets say, 50 IRE, it then throws 70 and 80 IRE out. Still got to learn how to adjust for one IRE while not messing up the others. Any way, I have attached my before and after file, please look at them and lend any advice you can, especially on the after file with trying to match up all the lines on the graphs. Thanks for any help.


Also, I have not messed with any picture or color controls yet, I am supposed to get the grayscale right first, then mess with those correct? I followed the dummies guide btw.

sotti
01-06-09, 09:44 PM
Well I don't have any good answers, but I have some questions for you that might lead to answers.

Do you have just blue and red brightness controls, or do you have RGB gain and RGB bias? You could really use adjustment both for high and low. If not I'd say raise red a little and lower blue a litte, but not much either way.

You should deffinetly check your contrast and brightness. You probably want to do those before during and after greyscale. Birghtness looks low.

hoops10
01-07-09, 07:32 AM
sotti: Here are the controls I have. They are R,G, and B Contrast (which I am assuming is what is also called RGBHighEnd) and R,G, and B Brightness (which is called RGBLowEnd). I will use the AVS HD disc again to set main contrast and brightness again, then re-run. BTW, I forgot to mention that I do have the dynamic iris on (which I am told gives better blacks, is that right?)

sotti
01-07-09, 12:59 PM
I'd turn off dynamic irs, I think that may be killing your ability to calibrate.

So what you want to do is this

Run the near white tests to set contrast so that you aren't clipping.
Once you have 100% field that doesn't clip use that max Luma to set your brightness to .00658 * max Lume on a 10% feild.
Double check contrast, double check brightness.

Now you've got your black and white levels set fairly well, go to grey scale. Since you've got high and low settings do this.

While (Error is out of tolerence)
{
Put up a 90% feild and set your RGB contrast settings
Put up a 30% field and set your RGB brightness settings
Double check Contrast/Near white
Double check brightness
}

You'll probably go through setting the contrast/brightness 2 or 3 times before you have your black level close.

Then depending on how out of what you white point is, you may do the whole greyscale/white level/black level set of tests another 4 or 5 times to get things as perfect as can be.


Another thing you may want to look it is how the setting work for color temp, I notice a drop in blue for the 60-70% range, that usually a something manufacturers do intentionally to keep skin ones close to natural while running 10,000K+ white points, so if you drop to the warmest setting they may automatically take that dip out.

hoops10
01-07-09, 07:25 PM
I have used the above recommendations and re ran my tests. I have attached the .chc file. Please take a look and let me know what you think or if there are any improvements that need to be made. One other thing, the guide that I was following (http://www.curtpalme.com/forum/viewtopic.php?t=10457) doesn't mention adjusting color, tint or sharpness that I know I had adjusted before when using AVIA, why is that? Am I supposed to adjust these after I get my greyscale calibrated? Thanks for all the help.

sotti
01-07-09, 07:39 PM
That looks like a pretty well calibrated greyscale.

Your gamma looks like it runs kind of high although some people like that. What you want from your Gamma has alot to do with how much light control you have in your room.

As for color, what controls do you have?
Color has two steps really,
Getting as close to the rec.709 gamut as possible.
Getting as uniform color as you can out of your actual gamut.

Since it's most displays can only get somewhat close to the acutal rec.709, you may want to calibrate your colors to be uniform with corect color decoding, that means your secondaries get derived from your native primaries, and the lumanance for all the colors change.

Accupel has a great free tool for this:
http://www.accupel.com/HDG4000_manuals.html

Display calibration calculator/

You may want the screen calculator as well.

hoops10
01-07-09, 07:51 PM
Here is what I have in my menu: Contrast, Brightness, Color, Tint, Sharpness and Color Temperature. In the past, I have calibrated color using AVIA and the color filters and used a combination of Color, Tint and Sharpness. Should I do the same using patterns from the AVS HD disc? Or can colors be calibrated using the ColorHCFR and the Eye-One LT?

HappyFunBoater
01-07-09, 08:07 PM
...One other thing, the guide that I was following (http://www.curtpalme.com/forum/viewtopic.php?t=10457) doesn't mention adjusting color or tint...

That guide DOES address color and tint towards the end. It talks about setting red Y to 21% of white Y. Then it talks about setting cyan to a specific x,y. This was added to the guide about six months ago, so maybe you have a REAL old version of it?

As sotti points out you can use the AccuPel tool to come up with a better value than 21% for red that takes into account your specific gamut (assuming that it isn't accurate), and better values for secondary x,y.

hoops10
01-07-09, 08:36 PM
Happy, I did read that part of the guide but I was under the assumption that it was only for displays that had an advanced CMS. I do not think my front pj has that.

Edit: Happy, all I have for color controls are color and tint. I tried using the Eye-One to get 21% of white but when I changed the color value just by one notch, I can't get the Y value close to that 21% of white number. I also tried calibrating the secondaries using the Tint and to get the x,y values close but again, with only one tool to adjust it (Tint), I can't get the x,y close to the numbers it should be. I did measure my primaries and secondaries but all their dE values were way high. Am I missing something?

If all else fails, can I use AVIA (SD) to calibrate Color and Tint?

HappyFunBoater
01-07-09, 09:37 PM
Happy, I did read that part of the guide but I was under the assumption that it was only for displays that had an advanced CMS. I do not think my front pj has that.

Edit: Happy, all I have for color controls are color and tint. I tried using the Eye-One to get 21% of white but when I changed the color value just by one notch, I can't get the Y value close to that 21% of white number. I also tried calibrating the secondaries using the Tint and to get the x,y values close but again, with only one tool to adjust it (Tint), I can't get the x,y close to the numbers it should be. I did measure my primaries and secondaries but all their dE values were way high. Am I missing something?

If all else fails, can I use AVIA (SD) to calibrate Color and Tint?

Yep, all I have are Color and Tint also. The reason you can't get close could be that your gamut is way off. In which case coming up with a new red Y% goal and a new tint x,y goal via AccuPel could be your answer. Have you tried that?

If you haven't played with AccuPel: Play around with it by pressing the button for Rec709, and you'll notice that it fills on all the x,y and Y% for RGBYCM. Notice that red Y% is 21%, and cyan x,y is the value recommended by the Guide (I forget the number). Fill in your white and RGB values on the bottom and press copy to move them up to replace the Rec709 values. Press Compute to get a new Y% for red. Play around with Color to get it as close as possible to this new Y% value. Now run HCFR again to get new RGB values, and hit Compute one more time to get YCM targets based on the current RGB values. Play with Tint to get as close as possible to the new YCM targets. It's kind of convoluted, and I wish it was part of HCFR. To be honest I don't know whether the Tint step is necessary given the accuracy of the probes we're using, but it's kind of fun just to play around with this stuff.

hoops10
01-09-09, 12:03 PM
Happy, thank you for the explanation of how to use the AccuPel in combination with HCFR. I think I got the primaries and secondaries as close as I can using only Color and Tint (which is shocking because all I needed to do was shift Color up 1 notch and leave Tint at the default 0 notch.) Do you know if there is a way to make graphs to see how close my primaries and secondaries are to D65? I tried in HCFR but it keeps showing the graphs from when I did my greyscale. Also is there a reason why White did not product a deltaE value. Anyway, my deltaE values for RBGYCM was:

Red - 19.6
Green - 18.7
Blue - 4.7
Yellow - 15.8
Cyan - 12.5
Magenta - 5.7

How do those look to you? If they are too far off, what else can I do to improve them?

HappyFunBoater
01-09-09, 12:22 PM
Happy, thank you for the explanation of how to use the AccuPel in combination with HCFR. I think I got the primaries and secondaries as close as I can using only Color and Tint (which is shocking because all I needed to do was shift Color up 1 notch and leave Tint at the default 0 notch.) Do you know if there is a way to make graphs to see how close my primaries and secondaries are to D65? I tried in HCFR but it keeps showing the graphs from when I did my greyscale. Also is there a reason why White did not product a deltaE value. Anyway, my deltaE values for RBGYCM was:

Red - 19.6
Green - 18.7
Blue - 4.7
Yellow - 15.8
Cyan - 12.5
Magenta - 5.7

How do those look to you? If they are too far off, what else can I do to improve them?

Can you post your CFC file from HCFR? I'm still a relative noob on much of this and am still learning the tools myself, but I can try to give some feedback. There are plenty of smarter folks on this forum that I hope will chime in regarding your questions. I'm fighting issues on my own TV trying to figure out which nobs and switches affect the HCFR readings. I'm about to dive into the service menu, but have been hesitant.

hoops10
01-09-09, 12:28 PM
No problem, attached is my cfc file.

sotti
01-09-09, 12:42 PM
No problem, attached is my cfc file.

Color decoding looks really good.

I don't know what one click up on color does but ever reading was a hair low, turning it up one notch could go badly in the other direction and be far too high.

Your color gammut is oversaturated vs the standard, but there really isn't much you can do to reign that back in without the right controls.

I responded to your PM about overall brightness.

You're gamma looks more like camera gamma with a 1.2 end to end gamma than normal 2.2 power function display gamma.

Gamma is a very tricky subject, and even when you arrive at the correct formula the absolute power for the formula still has alot of wiggle room based on viewing conditions. Since you've got a projector I'll assume very tightly light controled so for you that gamma ramp may be perfect.

hoops10
01-09-09, 12:51 PM
sotti: When I was taking measurements and calibrating color, I used the AVS HD disc. I used the 100% Saturated colors for the primaries and secondaries. Was that the right thing to do? I read to do that in the dummies guide. Should I have used different patterns on the AVS HD disc? On my projector, I do have High, Med. and Low Gamma controls, should I mess with those to try and tighten the gamma graph? Will messing with gamma mess up either my greayscale and/or my color settings?

HappyFunBoater
01-09-09, 01:37 PM
No problem, attached is my cfc file.

The dE on the RGB Levels looks great. Like you said, brightness is very low, but your gamma looks good. You must be be in a dark room. Like Sotti said, there's nothing you can do about the CIE gamut without a real CMS. The colors aren't that terribly oversaturated.

hoops10
01-09-09, 01:49 PM
Thanks again. One more question that deals with the dynamic iris. Once I turned off the dynamic iris, I was able to get the greyscale and color calibration pretty good, where it is now. If I turned it back on (to get better blacks), would my greyscale and colors now suffer or somehow get out of whack?

hoops10
01-10-09, 07:31 PM
Does anyone have an idea on what the dynamic iris would do? Ruin either/both the greyscale and color calibrations?

nicholc2
01-11-09, 09:58 AM
Does anyone have an idea on what the dynamic iris would do? Ruin either/both the greyscale and color calibrations?

Yes, that messes with grayscale, but most importantly gamma. Definitely leave that off.

hoops10
01-11-09, 01:23 PM
nicholc2, thanks for the response. Is it true that the dynamic iris gives you better blacks?

hoops10
01-12-09, 02:00 PM
Maybe someone can chime in here and explain this to me. If turning on the dynamic iris is so bad (that it kills your greyscale an ruins the gamma), then why do so many people use it? I have read many threads where people talk about the DI improving contrast ratio and giving better blacks. Am I missing something here?

nicholc2
01-12-09, 02:36 PM
Maybe someone can chime in here and explain this to me. If turning on the dynamic iris is so bad (that it kills your greyscale an ruins the gamma), then why do so many people use it? I have read many threads where people talk about the DI improving contrast ratio and giving better blacks. Am I missing something here?

If the TV is properly calibrated, then it shouldn't give better blacks. Also, remember, we're in the calibration forum. We strive for accurate results based on specifications. Dynamic Contrast changes levels on the fly which will mess with gamma and grayscale. This causes a picture that is not an accurate representation of the original source material. Dynamic contrast can also crush blacks and whites so you loose shadow detail.