The Official ChromaPure thread - Page 119

Hello,

For Color management, I use the 75% color patterns.
For advanced color management, I use the 100% saturation patterns. (With 25%, 50%, 75% and 100% saturation).

Sorry. Double post.

Triple post.

You don't use different saturation patterns to check the amplitude scale, which is colors of the same saturation but different levels of luminance..

I just got my CP/D3PRO combo and something isn't right. I had my Pio PRO-101 calibrated by Jeff Meir last night and here is the gray scale with the new D3 meter. It looked very much the same before calibration too. Got similar results in HCFR. My old DPT-94 looks much better.


bob postjeffgray.jpg 31k .jpg file

I can't speak for the D3Pro since I don't own one, but that isn't much worse than the difference I typically see between my Jeti and unprofiled C6.

Before taking some measurements, you should always wait at least 30 minutes for the screen AND the meter to heat up.

Spongebob has a plasma....probably be better to give it an hour.

I've also observed shifts in the i1dispay3pro during the first 30 minutes. Blue starts off high and gradually drifts downward.

It is not meter meter that is drifting. It is the display it's measuring.

Taking 30 minutes to get the display warmed up is a good idea. It is better practice to offset the meter from the screen surface several inches using a tripod, so it isn't affected by the display's heat.

It is impossible to intelligently respond to this since you have posted detailed information only about the results you got with the D3 PRO in CP. You need to also post the xyY data you got from the pro calibration and from using the D3 in HCFR and CM. It is impossible to compare numbers with anecdotes.

Yeah thats what I thought. Spot corrections for greyscale is easier than for the 125 point calibration.

The Price I pay for loving CRT !



Athanasios

Looks like I'm going to have to do another youtube clip to convince you. No hard feeling, it's just not been my experience.

That's fine. Just out of curiosity, since the meter has to measure something, and all you can do is show the measurements, how can whatever you show demonstrate that any change is due to the measurement equipment as opposed to the display being measured? The only way I can think of is to measure with one meter and then immediately measure with another meter, wait 30 min., and then remeasure with both. If the results show that meter A shows different readings but meter B doesn't, then that would be strong evidence that meter A has drifted.

However, think about this for a moment. What exactly is the theory behind a meter drifting in 30 minutes--over 6 months maybe--but over 30 minutes? The only scenario I can think of in which that might happen is if you were doing a contact measurement. After 30 minutes, the heat from the display could, and likely would, heat up the colorimeter, which could very well alter its response. This is exactly why I recommend taking readings from a tripod offset far enough from the screen so the radiated heat of the display does not influence the meter.

The meter is, after all, a passive device that only reports what it "sees". The display, on the other hand, is actively creating the image you see and it will certainly drift during the first half hour of use. That's why you should always warm up the display prior to calibrating it.

I know the Experts say you only have to Warm up the set for 45 minutes to an hour, but, as an experiment, I calibrated my set. Turned it off overnight, then turned it back on the next day, then took readings every half hour. On my older set (3 Yrs old), the readings didn't come back up to the previous nights settings until 4 Hours later! Tried my newer set in the basement with same experiment - it took 3.5 hours to come back up to the previous night's calibrated settings.
The newer sets gradually have a lifting Blue, and as it gets older, a lifting Red with a little bit of rising Blue. The sets are all LCD/LEDs.

OK, I have demonstrated this many times now, but apparently it is necessary again.

The first report shows a grayscale run from 30-100% using the JETI 1201 reference spectro. The display is a Pioneer 5020.
The second report shows the same measurements of the same display, but this time with a Display 3 PRO, whose corrections were created by our lab plasma, which is a Panasonic ST30.





They are almost EXACTLY the same, despite the fact that the corrections were created on a different make and model plasma than the one being measured. Here are the same readings of the same Pioneer, with the same meter, but without the PRO corrections.



The difference is not night and day, but clearly discernible.

A little more specificity would help here. How much difference did you see after 1/2 hour?, 1 hour?, etc. I tested this on a Samsung LED and saw very little change after 30 minutes. Admittedly, I stopped measuring after 1 hour. Between 30 min. and 60 min. the readings had varied by only 0.001, which is negligible. But the difference between start and 30 min. was 0.003 in the y axis, which is still very small.

http://www.avsforum.com/t/852536/basic-guide-to-color-calibration-using-a-cms-updated-and-enhanced/1700_50#post_21779935

BTW, another problem with a 4 hour warm up time (even if technically justified), aside from the obvious practical limitations, is that this exceeds the length of many viewing sessions, in which case you may be calibrating to a target that is rarely actually used in the real world.

I'm sorry for jumping the gun but I kinda freaked out; Either my new calibrated meter is off or the Calibrators' meter is off. Either way, I lose. I'll wait for his report and try and provide more data.


So, does the D3 PRO meter need to warm up on the plasma screen or not?



bob

The reason I went to this, I was fed up of calibrating the Greyscale after only a half hour of warm up, only to find doing a complete reading, all the points had all changed in the time of calibrating from 100IRE down to 10. (Yes I realize there will be discrepancies - this is why I do 3 calibrations - First to get all the points within the Ballpark, 2nd to get the settings into the Stands, and finally the 3rd to get the settings onto the Actual Playing Field, then maybe a fourth to put all the settings into the actual Diamond Area). So, was left still in the Ball Park, but not the Stands. Now that a couple of hours have gone by, the settings are finally falling into place. By waiting 3 to4 hours - I'm into the Actual Playing Field, if not the Diamond area within max of 3 calibrations, that also took less time, with less spikes and dips. Maybe it's my sets, but this is what I've found best in my situation. Still looks great on turn on, but keeps getting better as I watch. Have noticed since getting to spec, the viewing is great within the half hour.

how do I calibrate for 3D? I mean, do I have to activate the glasses to ''shutter''? And do I just hang the glasses in front of the meter?

Hello, so basically one hour warm up is plenty for a plasma.

Not. Do NOT put in on the plasma. Pull it back a foot or so using a tripod.

OK, I tried this again on the same Samsung LED.

In the first test linked above, I let it warm up for an hour and the x-axis was down 0.002 and the y-axis was down 0.004. Luminance was down by 2.8%. In the second test this evening, I left it on for six hours and x was down an additional 0.001 and and y was down additional 0.002. Luminance was down an additional 1.6%. This is a negligible difference. The more interesting question is whether 30 minutes is adequate. After 30 minutes, x was down 0.001 and y was down 0.003.

Start:........x0.305, y0.327, Y112.9
30 min:.....x0.304, y0.324, Y111.1
60 min:.....x0.303, y0.323, Y109.7
360 min:...x0.302, y0.321, Y107.9

At least on this unit--I could try it on a Sony and and LG if anyone is interested--the bottom line is that the LED display gets slowly dimmer as it is left on for long periods of time, getting a little bluer and redder along the way. However, after 6 hours, the difference is small, a dE in the 2-3 range and a little over 4% dimmer. About half of that change occurs in the first 30 minutes. In my opinion, the remaining half offers just too small an additional change to merit additional wait time, but if you want to wait longer it certainly doesn't hurt.

If you have no problems with the meter reading through the glasses and you can get test patterns into the display while it is in 3D mode, then yes this is fine.

Yes, this is possible. But two more questions:


Do I put the lens of the right (of left) of the glasses as close as possible to my i1 Display Pro III meter?
Do I put ON the glasses so it shutters or not?

And Here is a new measurement I just did. What you guys think of the Grayscale I achieved? Is there room for improvement? And what about the gamma? Should I aim for a 2.4-2.5 gamma for a complete darkened bat cave?

Next thing I want to do is the CMS. I have a Sony HW50 projector and I can adjust the Red, Yellow, Green, Cyan, Blue and Magenta. But I have quite some parameter I can adjust per color. I can change the POSITION and RANGE. Do I just this this for all colors on default? And next I can change the COLOR, HUE and BRIGHTNESS for each color. Where do I start with adjusting? The Curtpalme guide for Grayscale was pretty straightforward and simple to understand but there not a really good CMS guide. I also cannot find a step-by-step guide for the parameters I have that can be adjusted how they exactly work and which steps are best to run through.

1.jpg 91k .jpg file

2.jpg 73k .jpg file

It does not matter which side (left or right) that you use. The big trick is getting the glasses to stay on. I have, at times, rigged up a scheme of paper reflectors tp direct the emitter's IR up towards the glasses, and another on the glasses to help capture the IR.

? On the Sony HW50 you can enable 2D to 3D conversion which makes 2D (like the AVS HD709 test discs pattern) show in 3D.

That might be the problem. I let it warm up for at least a half hour and then ongoing for at least an hour on a torchy Elite.

Could it affect accuracy or just longevity?


bob

?? about the ?:
My point was about keeping the glasses "seeing" the IR Sync signal. (Not about getting the set in the 3D mode). Often, the probe is placed fairly close to the screen, so glasses placed in front of the probe may be too close to "see" the IR emitter.