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The Official ChromaPure thread - Page 131

post #3901 of 4333
2/15/13 at 7:45am
Visually, should a 10 step grayscale calibrated to D65 standard appear as a neutral gray?
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post #3902 of 4333
2/15/13 at 11:29am
Quote:
Originally Posted by realzven View Post

your greyscale is good, like low end meters the results of the D3 PRO is not totally accurate below 30%... wink.gif
The D3 PRO has no problem with accuracy at low light levels. It can have a problem with repeatability, but only on plasmas and only below 1 cd/m2, which is typically 10%.
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post #3903 of 4333
2/15/13 at 11:32am
Quote:
Originally Posted by JimP View Post

Thanks for the firmware update on the Accupel 5000.

Having an option of changing the size of window patterns is a great feature. I've already changed mine to 5%.

For those who haven't followed Chad B's thread, a 5% window size seems to work best on the Panasonic VT50 plasmas. That's to minimize having the ABL circuit affect your readings at higher lumanance levels.
Yea, it is a good feature to have. Because of the AccuPel's architecture this was actually harder to do than I would have thought. In the next version of CP, we'll add a small window option to the AccuPel setup that will use the 5% size.
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post #3904 of 4333
2/15/13 at 11:41am
Today I calibrated my vt50eu by hand with the small lumagen windows. What happened is that the 100ire window required a really low contrast to be at 35 ftl. It had to be at 30 when normally it is at 37 to 42. Also, chromapure measures my gamma way to low compared to what the tv is set to. I have to set the tv to 2.6 to get anywhere near the 2.22, and even then all the ire point have to be cranked way up gamma-wise cause they're all way too bright. Now here's the annoying thing, once I've done all that, the graphs are all pretty, but the image with bluray or cable video is just visibly too dark... I trust the chromapure gamma reading, not the tv setting, bit it seems the abl is making it difficult. Any suggestions on how to tackle this? I got the best results in the past with small windows with an apl background, but I want to use my 125 color calibration and those patterns aren't available.
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post #3905 of 4333
2/15/13 at 1:10pm
Quote:
Originally Posted by realzven View Post

your greyscale is good, like low end meters the results of the D3 PRO is not totally accurate below 30%... wink.gif

If calibrated against a good spectrometer the Display PRO is very accurate down to 10%. I've measured the precision (repeatability) at +/- 0.6 dE(uv) 3-sigma on my plasma at those levels so if it's got a good reference calibration it's going to be accurate.
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post #3906 of 4333
2/15/13 at 1:39pm
Quote:
Originally Posted by TomHuffman View Post

The D3 PRO has no problem with accuracy at low light levels. It can have a problem with repeatability, but only on plasmas and only below 1 cd/m2, which is typically 10%.
So, would you advise me to calibrate from 20% and 80% like you say in your manual ?
I did it from 30% because 40% was not good at all when calibrating from 20%. (Plasma P65ST50 using Small APL patterns)

Here's my dE chart :


BTW, did you get my email ? (Jumpy results solved by not selecting any modes to APPLY)
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post #3907 of 4333
2/16/13 at 2:24pm
I calibrated my BenQ W7000 and thought it turned out pretty good. Gray scale and all colours except green turned out almost spot on. The one issue I have is with Gamma. The W7000 doesn't have custom gamma (only selectable...2.2, 2.4 etc. ) so is there a good way of trying to adjust gamma with any other controls? 90% reads pretty high and 10% measures pretty low.

With green not hitting where it's supposed to be, which one of the xyY is best to sacrifice? right now I have hue that's out

edit:

I figured out the gamma by using the brightness and contrast controls.

edit #2:

WoW! I just redid another calibration with awesome results! My BenQ never looked better! I can now watch a bluray and be almost as happy as when I watch with my JVC X-55......almost.

Thanks Tom! well worth every penny spent.
Edited by Crabalocker - 2/16/13 at 7:11pm
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post #3908 of 4333
2/17/13 at 12:21am
You should not use contrast/brightness to set gamma. I just checked the manual for your projector, and can see you only have gain/cutoff's available, In that case you might be lucky to be able to do it with them(I know people will disagree and say that gain/cutoff' work the same way as brightness/contrast - But I have succesfully sorted a simiar issue on my display using gain/cutoff') tha advantage doing this is that you dont comprimise the black and white level.

try to set brightness and contrast correctly first and then redo the white balance (20/30 - 80 but use the gamma module in CP lowering/raising ALL 3 colors(gain/cutofff) should raise/lower your gamma
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post #3909 of 4333
2/17/13 at 5:28am
Is it better to be using 20 % white stimulus and 80 % white stimulus to do the 2 pt white balance compared to 20 /100? any advantages/disadvantages?
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post #3910 of 4333
2/17/13 at 6:00am
For a two point it simply depends on which gives you the best results. It will depend on the display and one should try both. My guess is that 20/80 will work best because the deltas are smaller between the two points splitting 20/60/20 rather than 20/80/0. If you really want to knock yourself you can try 30 and 70 instead of 80 too.There is no right, it what gices you the straightest color temp line closest to 6500.
Edited by mark haflich - 2/17/13 at 8:05am
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post #3911 of 4333
2/17/13 at 6:20am
Quote:
Originally Posted by hungro View Post

Is it better to be using 20 % white stimulus and 80 % white stimulus to do the 2 pt white balance compared to 20 /100? any advantages/disadvantages?
I only use 20/80 as a starting point to get quick and still a bit dirty results.
But for the final calibration I look at all the lower IRE's (1--50) for the offset setting, and all of the higher IRE's (60-100) for the gain setting. So basically looking at the complete greyscale and check for best offset and gain.
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post #3912 of 4333
2/17/13 at 9:52am
Quote:
Originally Posted by visca blaugrana View Post

You should not use contrast/brightness to set gamma. I just checked the manual for your projector, and can see you only have gain/cutoff's available, In that case you might be lucky to be able to do it with them(I know people will disagree and say that gain/cutoff' work the same way as brightness/contrast - But I have succesfully sorted a simiar issue on my display using gain/cutoff') tha advantage doing this is that you dont comprimise the black and white level.

try to set brightness and contrast correctly first and then redo the white balance (20/30 - 80 but use the gamma module in CP lowering/raising ALL 3 colors(gain/cutofff) should raise/lower your gamma

I use the gain and offset to correct the gray scale colours (white point). If I use these later to do the gamma won't that change the colour of gray?

Right now, after adjusting the gamma the best I can using the B&C controls, my brightness is set at 52 and contrast is set at 49 (50-being the standard starting point), which is what it was set at when I used the Disney wow disc to set my B&C before I got ChromaPure. Coincidence? does having the proper brightness and contrast actually help give a proper gamma curve? I think that's a rhetorical question. I know the THX calibrator that did my X-55 never touched brightness or contrast but used custom gamma to get everything close. That's why I didn't set B&C during my calibration and only tweaked them trying to fix the gamma, no custom gamma controls. I still have lots to learn.

I still love how easy it is to use ChromaPure and how good the picture looks when you're done. My eyes were nowhere close to being accurate.
Edited by Crabalocker - 2/17/13 at 9:58am
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post #3913 of 4333
2/17/13 at 12:03pm
Did anyone catch Home Theater Geeks's Episode #148 on Color Output versus White Output ?
Very interesting . There was a Link to www.Lumita.com where these measurements were taken for the Episode and there are quite a few Papers describing the process .
The actual procedure for measuring and determining this Color Output Value is described in their Paper....http://www.lumita.com/site_media/work/whitepapers/files/New_IEC-proposal_1207.pdf
I'm wondering what Tom thinks of this ? Is it something that can be incorporated into a future CP release ?

Scott...............smile.gif
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post #3914 of 4333
2/17/13 at 12:05pm
Quote:
Originally Posted by Crabalocker View Post

I use the gain and offset to correct the gray scale colours (white point). If I use these later to do the gamma won't that change the colour of gray?
Not if you use them all. First, adjust green. It will have the biggest effect on gamma. When you get it where you want it, then adjust red and blue to regain proper white balance.
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post #3915 of 4333
2/17/13 at 1:25pm
Ok, round three.
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post #3916 of 4333
2/17/13 at 2:09pm
Life is all about gaining and maintaining the proper balance, White point balance is no different just easier.
Edited by mark haflich - 2/17/13 at 11:35pm
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post #3917 of 4333
2/17/13 at 5:48pm
Quote:
Originally Posted by Scott_R_K View Post

Did anyone catch Home Theater Geeks's Episode #148 on Color Output versus White Output ?
Very interesting . There was a Link to www.Lumita.com where these measurements were taken for the Episode and there are quite a few Papers describing the process .
The actual procedure for measuring and determining this Color Output Value is described in their Paper....http://www.lumita.com/site_media/work/whitepapers/files/New_IEC-proposal_1207.pdf
I'm wondering what Tom thinks of this ? Is it something that can be incorporated into a future CP release ?
There's nothing additional to incorporate. CP has included information about color luminance as well as white luminance from the very beginning. This is reflected in dE and specifically documented as luminance and lightness errors.
Edited by TomHuffman - 2/17/13 at 11:53pm
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post #3918 of 4333
2/17/13 at 6:17pm
I must say the more I read about plasma calibration, with regard to pattern size, the more confused I have become. It seems especially troubling with regard to using DUO and Radiance as pattern generators for auto-calibration.

Will Chrompure support smaller windows sizes on the mainstream video processors for plasma auto-calibration?

All the discussions in other threads about what happens with gamma and brightness limiters seems to question the validity of any calibration let alone a cube.

It would be interesting to see how the competing 125 point auto-calibration apps benchmark against each other both in terms of accuracy and length of time to hit targets.
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post #3919 of 4333
2/17/13 at 7:26pm
Quote:
Originally Posted by gtgray View Post

I must say the more I read about plasma calibration, with regard to pattern size, the more confused I have become. It seems especially troubling with regard to using DUO and Radiance as pattern generators for auto-calibration.

Will Chrompure support smaller windows sizes on the mainstream video processors for plasma auto-calibration?

All the discussions in other threads about what happens with gamma and brightness limiters seems to question the validity of any calibration let alone a cube.
Yes, but it is easy to exaggerate the importance of this. The differences are subtle but worth accounting for. It makes a difference at the margins only.
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post #3920 of 4333
2/17/13 at 11:42pm
The whole consumer calibration industry is based on a need for perfection. A desire to roll 300 or pitch a perfect game. Anybody can buy the equipment etc and spend countless hours about chasing des of 0 and calibrating 124 points instead of 7. Its most just a game. Not calibrating in general but chasing marginal improvements or theoretical ones. Worth it becomes in the eye of the beholder. With automatation the time factor vanishes for self calibration. You can always do something else Even take a nap.
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post #3921 of 4333
2/18/13 at 6:30am
Quote:
Originally Posted by Scott_R_K View Post

Did anyone catch Home Theater Geeks's Episode #148 on Color Output versus White Output ?
Very interesting . There was a Link to www.Lumita.com where these measurements were taken for the Episode and there are quite a few Papers describing the process .
The actual procedure for measuring and determining this Color Output Value is described in their Paper....http://www.lumita.com/site_media/work/whitepapers/files/New_IEC-proposal_1207.pdf
I'm wondering what Tom thinks of this ? Is it something that can be incorporated into a future CP release ?

Scott...............smile.gif

I saw this and it was immediately clear this was a strategy to achieve a marketing advantage in lcd based front projectors at a given price point. White lumens vs. Color Lumens. LCOS vs. DLP. While it was interesting about the theorectical advantage in the real wold if you are getting 16 ft lamberts of max white and the kind of color dEs we are routinely seeing now with good CMS impementations it really doesn't matter. I think this is of most interest in the very low end of the home theater projection market. There are many storied single chip DLP projectors Joe Kane's Samsung special editions for example. Clearly the success of the JVCs and the Epson/Panasonic projectors is sort of testimonial to this advantage but I think they are more successful not because of the higher color lumens but because of the very hight native contrast.
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post #3922 of 4333
2/18/13 at 4:22pm
Ok, what am I missing? I am using ChromaPure (CP) with a meter and the DUO to try and calibrate a VT50. The way things connect, it seems like I am calibrating the Duo instead of the tv. I initialize the meter and the Duo but do not see anywhere to connect the tv and CP. With the way I am doing it now, nothing changes in the tv settings and the reports that are generated bare no resemblance to the mode settings in the tv. With Calman 5, at least you have to setup a remote connection with the tv. Still trying to figure out how to run that program by the way.

As an aside, I find the lack of a printable manual for these calibration programs very frustrating. I like to read through a manual ahead of time to figure out what I need to do. The HELP screens are nice for those that know what they are doing, but for a complete novice like me, not always helpful. Many times the question I have is not answered by HELP. My problem may be that I am completely over my head. I wanted to be able to calibrate my tv beyond Disney WoW but not have a professional come in. Came to forums like this and discovered ChromaPure and CalMan 5.. The next thing I saw was AUTO-CALIBRATION! Man, what more could I ask for. So, I jumped in with both feet, and here I am. It almost seems you need to calibrate the tv manually before you do it automatically. I suppose most folks prefer to do it manually anyway.

Sorry for rambling. I sincerely appreciate any help.

Best Regards,

Steve
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post #3923 of 4333
2/18/13 at 4:38pm
Quote:
Originally Posted by Thunderduck View Post

Ok, what am I missing? I am using ChromaPure (CP) with a meter and the DUO to try and calibrate a VT50. The way things connect, it seems like I am calibrating the Duo instead of the tv. I initialize the meter and the Duo but do not see anywhere to connect the tv and CP. With the way I am doing it now, nothing changes in the tv settings and the reports that are generated bare no resemblance to the mode settings in the tv. With Calman 5, at least you have to setup a remote connection with the tv. Still trying to figure out how to run that program by the way.

As an aside, I find the lack of a printable manual for these calibration programs very frustrating. I like to read through a manual ahead of time to figure out what I need to do. The HELP screens are nice for those that know what they are doing, but for a complete novice like me, not always helpful. Many times the question I have is not answered by HELP. My problem may be that I am completely over my head. I wanted to be able to calibrate my tv beyond Disney WoW but not have a professional come in. Came to forums like this and discovered ChromaPure and CalMan 5.. The next thing I saw was AUTO-CALIBRATION! Man, what more could I ask for. So, I jumped in with both feet, and here I am. It almost seems you need to calibrate the tv manually before you do it automatically. I suppose most folks prefer to do it manually anyway.

Sorry for rambling. I sincerely appreciate any help.

Best Regards,

Steve

You need a USB to RS-232 adapter and an appropriate serial cable. These connect a USB port on the computer where you run CP and to the serial port on the DUO. CP needs to be setup under Options> Signal Generators to enable the control of the DUO by CP. Both the DUO and your Com Port on the computer need to be at the same bit rate, partiy, stop bit etc. Once that is done CP can operate the DUO and use it as a signal generator and allowing you to do an auto-calibration. I hope you understand that the HDMI out on the DUO is the main conduit for your source devices to get their signal into your display. The DUO if allowed modifies the signal before it sends to your TV it does not actually calibrate your TV. It adjusts white and colors in the signal to compensate for your displays deviation from reference response tothe input signal.

Plasmas are trickier than other types
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post #3924 of 4333
2/18/13 at 5:20pm
Quote:
Originally Posted by Thunderduck View Post

As an aside, I find the lack of a printable manual for these calibration programs very frustrating. I like to read through a manual ahead of time to figure out what I need to do. The HELP screens are nice for those that know what they are doing, but for a complete novice like me, not always helpful. Many times the question I have is not answered by HELP.
http://www.chromapure.com/ChromaPureManual.pdf
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post #3925 of 4333
2/18/13 at 9:23pm
Tom,

Is there a way to change the 6500K target to say 7000K within CP? I went through the menu and couldn't find it. I need this to develop some display profiles.

Thanks,

Slimer
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post #3926 of 4333
2/18/13 at 11:07pm
Quote:
Originally Posted by slimer777 View Post

Tom,

Is there a way to change the 6500K target to say 7000K within CP? I went through the menu and couldn't find it. I need this to develop some display profiles.
Not currently.
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post #3927 of 4333
2/18/13 at 11:15pm
Quote:
Originally Posted by turboman123 View Post

Thanks Tom for the reply. I tried out a few things.
Following is a greyscale on my panel with Contrast setting 84 compared to 80. Clearly 84 causes red clipping, and 80 not. Just a small change in gamma though, but clipping is easier to recognize in the greyscale I think.
CalibrationSummaryDetailed-Clipping.pdf 1323k .pdf file

Of course, these are only measurements in 10% steps. So question is, where does clipping begin exactly.
For that I made measurements with AVSHD near white patterns: 96%, 97% etc until 100%. For convenience, these measurements were put on the graph at 60%, 70% up to 100%.
First a measurement with clipping at Contrast 84. Then another measurement with Contrast 82, which shows that 99%peak white does not show clipping, but 100% shows clipping. That would show me that Contrast 81 would just completely avoid clipping.
CalibrationSummaryDetailed-Clipping-Fine.pdf 1303k .pdf file

Tom: how do you consider this procedure? Does it do the job as good as SM or AVSHD visual clipping pattern observation? I think this measurement procedure is better, less subjective, less dependent on panel uniformity or viewing angle.

Tom: could you have a look at this please. What do you think about this procedure?
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post #3928 of 4333
2/19/13 at 3:10am
Here are my reports for my Sony LED 55HX950 if anyone would like to comment or make suggestions that would be great. My TV does not have CMS.

Thanks
Vince


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post #3929 of 4333
2/19/13 at 6:04am
Quote:
Originally Posted by TomHuffman View Post

http://www.chromapure.com/ChromaPureManual.pdf

Thank you so much!!
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post #3930 of 4333
2/19/13 at 6:16am
Quote:
Originally Posted by vtalon View Post

Here are my reports for my Sony LED 55HX950 if anyone would like to comment or make suggestions that would be great. My TV does not have CMS.

Thanks
Vince



All your dE's are below the visible threshold, which is 1.8. The only one that isn't is blue, which happens to be the color with which errors are least noticable.
So, your charts look near perfect. If your image also looks good to you, and you do not see visible errors that are related to your calibration and not to the source, I'd say don't touch it anymore.
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