The Official ChromaPure thread - Page 7

I have no problem with installing my Chroma5 on the LCD screen, but will the heat of the Plasma screen damage or cause other problems with the meter? If so, on Plasma screens should the meter be kept off the screen?

It won't damage it, but on the other hand minimizimng exposure to swings in temperature will probably extend its life. Thus, putting it on a tripod a few inches from the screen certainly wouldn't hurt.

Flatlined the Green from 100IRE to 10IRE and the PQ looks great. I'm using the Chroma5 with the Calman software and have changed the Grayscale Formula to 1996 and the DeltaE to 2.22. Problem begins when I try to pull the Blue down to the Green - my nice 100% white screen starts turning Yellowish the closer the Blue gets to the Green. I'm I missing a change that needs to be made in the software settings? Have tried changing various settings but the Blue still stays aloof and doesn't want to flatline without creating the yellowish tinge. Any suggestions?

If you're actually using CalMAN then posting in a ChromaPure thread isn't your best bet.

How can I try the Chromapure to see if I'm having the same problem? Others are trying to tell me the Yellow tinge is natural and to get used to it - that's what 100% white looks like - the meter doesn't lie!

Yellow tinge is not natural and 100% white really looks WHITE. Maybe your meter is not working good and is lying.

Federico

The meter can lie if the meter itself is out-of-calibration.

If you are running grayscale adjustments, make sure you adjust the upper end first. I've seen where adjusting the low end first can throw things off. And you are not trying to get Blue to match Green. You are trying to get all colors (Red, Green, Blue) to their correct percentage make-up for a true D65 color temperature. You need to adjust all colors (or at least two of the three, depending on your controls) at the same time for the upper end and then the lower end. And then go back and re-iterate several times since there is some small inter-play between upper and low end adjustments.

Finally, it is not uncommon for people accustomed to non-calibrated displays and watching in the "dynamic" or "vivid" torch modes to think that a calibrated D65 white is yellowish. The fact is that the torch modes have a very cold (blue) color temperature.

Both CalMan and Chromapure will yield the same results.
TV sets have inherent flaws and the best way to discover those is with this:
http://hometheatermag.com/advicefrom...s_and_munsil/#
$25 at Amazon

Spears and Munsil is not your basic pattern disk, it is a test disk designed to reveal inherent flaws in the electronics and the panel

Go to page 2 of the hometheatermag and read the first 2 paragraphs dealing with contrast setting problems. My LG does show some deficiencies.

[quote=stash64;18060186]The meter can lie if the meter itself is out-of-calibration.

If you are running grayscale adjustments, make sure you adjust the upper end first. I've seen where adjusting the low end first can throw things off. And you are not trying to get Blue to match Green. You are trying to get all colors (Red, Green, Blue) to their correct percentage make-up for a true D65 color temperature. You need to adjust all colors (or at least two of the three, depending on your controls) at the same time for the upper end and then the lower end. And then go back and re-iterate several times since there is some small inter-play between upper and low end adjustments.

Meter was shipped to Spectracal who then shipped it back to me saying they couldn't find anything wrong with it. `Working Perfectly!' Maybe the problem is that some of us are more sensitive to Yellow than others?

I wouldn't call it a sensitivity to yellow but being "conditioned" to a very bluish white (in the case of those who just leave their newly purchased TV's in the video mode it was set to as default by the factory). If this is your first time calibrating your set, you probably have been conditioned towards blue whites.

Why don't you just complete your calibration based on what the software and meter are giving you and then just try it out for a few weeks. Do some critical viewing with HD (BluRay) content paying particular attention to skin tones. I'd be surprised if you don't come to the realization that everything now looks more natural. And if you still don't like the warm D65 setting after a few weeks, aim for a higher color temp (say 7000K or 7500K) in your next round of grayscale adjustments.

Have been calibrating a LG 55LH90 July build since last Aug and a Nov build since November. Was always disappointed with the overall yellow haze on both sets after Grayscaling to 2.22 Gamma and optimizing the CMS. One day, feeling a little lazy, flatlined ONLY the Green component. Lo and behold, loved it! No yellow haze, my HD DVDs and Satellite were gorgeous and the BBC Blu-rays were stunning. Several others who did only the Green also liked the PQ. Others prefer the whole calibration look - so, beauty is in the eye of the beholder. The other problem, other than the whole lot of time trying to get the total calibration done, was the drifting values that needed to be continually re tweaked taking more time. The Green flatlining drifted very little and can be completely done in 20 minutes without arm twisting the LG.

Not sure what you mean by "flatlined" but it doesn't sound right. If you haven't done so, I still suggest you try the grayscale adjustments again. Set all white balance controls back to 0 or default and then make sure you start your adjustments from the upper end first. With my Sony SXRD I would get different and wrong results if I started adjusting from the low end first. I ended up with reddish blacks. That would be another thing to check. Look at whatever you use for black level adjustment and make sure the blacks don't have any hint of color.

Given that you have new TVs you can certainly expect them to drift for awhile and will probably need to re-calibrate in another few months. I think most ISF techs will tell you not to bother with a full calibration until you have a certain minimum of break-in hours.

Always calibrate from the 100IRE to 10IRE - Calibrate the Green Component first from 100 to 10 to the 2.22 Gamma, then try to pull in the Red and Blue. Always Zero all IRE and CMS settings first. Set the DeltaE to 2.22 and the Grayscale Formula to 1996. White Balance to Warm. (White Balance on either Medium or Cool - Red and Green won't pull into the Gamma 2.22)

Maybe it's time to change the Mindset

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To some what qualify myself, I own and run a successful computer shop. What does this have to do with calibrating my LG 55LH90s, namely I sit and look at WHITE monitor and WHITE Laptop screens all day! Now to come home and sweat over getting my LG calibrated only to find the over all picture has a YELLOW tinge to it and to read others on the Forum have also found the same: then have people tell me the Yellow tinge is because I'm used to a different kind of white and that I'll get used to it, it won't be as bad once you look at the Big picture, the meter never lies, the charts and diagrams says I'm at The Perfect White and other let's fool myself into thinking that what I'm seeing is right. NO! There's something wrong here!
Question #1 - Why is the Green so easy to calibrate but not the Red and Blue? #2 - What is causing this difficulty - is it the way the electronics are setup in the LG #3 - OK, maybe we are calibrating to the perfect so called White to only find a Yellow tinge - then maybe the human phsyiology is not meant to see this so called Perfect White? Then maybe it's time to calibrate to the Human Physiology! Just my thoughts.

this is very wrong...and not grounded in any type of imaging science.

Gamma has nothing to do with the green control. (cuts and gains).

And what if ALL of those monitors and laptops were shipped from the factory with white points shifted considerably towards blue? This is not speculation. I have calibrated over a hundred displays and almost without exception prior to adjustment the white point is shifted towards blue. Any experienced calibrator will tell you the same thing. So this is the color of white that you have become accustomed to seeing. What would happen if that blue bias were suddenly removed? The shade of white would now appear relatively yellow (yellow is the opposite of blue).

That's my explanation for what you are seeing. You don't like this explanation. That's fine. What's your alternate explanation?


The vast majority of the light output of the panel is in the green channel. It is the most stable and most linear. Again, this is almost universally true.

Since you are not a ChromaPure user and your questions are not about ChromaPure, may I gently suggest that you start another thread to pursue this further?

There is now a thread on the xxLH90 calibration here:
http://www.avsforum.com/avs-vb/showthread.php?t=1221950
Also applies to the LG LH 50 and 40 since these have the same picture calibration controls.

Having calibrated my 55LH90 on HDMI 1 and 4 with ChromaPure and a Chroma 5 many times , I can attest that there is no yellow tinge if calibration is done correctly.

Using the Spears&Munsil BR test disk there are problems with some BR players:
http://www.avsforum.com/avs-vb/showp...5&postcount=66

The Spears&Munsil disk demo there is a scene where a ferry crosses the bay. The ferry hull is white. On my 55LH90 that hull is as white as fresh snow. After calibration with ChromaPure.

If users would consult these sites:
http://www.chromapure.com/colorscience-3dimensions.asp

http://www.displaycalibrationonline....ices_guide.asp

They would get a good education

If I read your method correctly, it is all wrong. When adjusting grayscale you should just be concentrating at getting "all" 3 colors to the correct percentage at that particular IRE.

Here is where ChromaPure can be a big advantage in my opinion. I've used HCFR and also had a trial of Calman for a couple weeks. I got my hands dirty and learned how to calibrate using HCFR before trying Calman. I found HCFR to be easy to use and fairly intuitive but Calman has a steeper learning curve, probably because it was initially designed for professionals. If I had started with Calman I think it would have taken me longer to learn the basic process. ChromaPure is designed with the home user in mind and I believe does a better job of stepping the beginner through the whole process and in the correct order.

As stated above, check out the ChromaPure website and run through all the demos. It will give you an idea of the whole process even though you are not using ChromaPure.

Time to learn something new - will give the ChromaPure a try! Thanks

Having used HCFR for close to 4 years I can say it is a very good program and the price is right.
But, HCFR lacks the professionally designed workflow, the builtin help, meter support and the report generators present in ChromaPure.
The author of ChromaPure has years of calibration experience and has distilled that experience in ChromaPure. The result is a guiding helping hand for the enthusiast novice.

The HCFR user is on his own in determining the workflow to use although there are threads here that will guide the beginner.

Not to bash CalMan, it is excellent software as well but IMO has a steeper learning curve for those wanting to use the advanced features.

My recommendation is to start with ChromaPure.
Then if the need for custom layout design and report customization becomes important one can always add CalMan.

I also would presume that these calibration software authors all use accurate colorscience conversion math as standardized by CIE, SMPTE and Poynton.

http://www.poynton.com/
http://www.poynton.com/notes/PU-PR-I...n-PU-PR-IS.pdf

When in doubt, consult an authority

Installed the Chromapure last night and set out to do my first calibration after letting the LG warm up a little over an hour. This software definitely shows up that one should let the set warm up for several hours before calibrating. At 100% White - Red had to be put up to the top (50) to bring it Up even with the Blue and Green. Did the complete 100IRE to 10IRE in a far shorter time frame than with the Calman and no arm wrestling! Let values settle in while I watched several hours of Caprica and a BBC Blu-ray. Went back to 100% White and now the Red was brought back Down to the Blue and Green - value was now 24. Blue and Green had little variation over this viewing period. Definitely a totally different set of values in the ChromaPure versus the Calman settings. Didn't have the oscillating problem either versus the Calman. Yellow tinge gone to be replaced with a very slight tinge of Red, but seeing where the Red settings were going, I was sort of expecting it. Did not get the whole 100IRE to 10IRE completed - 1 AM is my limit when I have to get up the next morning! But it again it brings up the question, why does a Solid State device have to have so much warm up time? (The Chroma5 was installed on the screen the whole time to allow both to warm up together.) Will let warm up several hours tonight and try to complete the 100IRE to 10IRE.

Currently now calibrating with the ChromaPure - definitely different settings than I got from Calman. It is more stable, still not simple, but progress is easier in that I was getting some kind of oscillating effect that had the settings bouncing up and down with the Calman, not having the problem with the ChromaPure. Purchased a new 55LH90 assuming the problem was with the LG. The oscillating effect calmed down, but still there. Sent Chroma5 back to be checked - returned as A-OK. So now that I've gone to the ChromaPure, and not having the problem: I assume it was something in the Calman causing the problem. As far as the Monitor and Laptop screens I watch at the store all day - I do not see any variation from screen to screen, if it's there, it's very slight, but in watching these all day, guaranteed it's going to affect how I watch my LG when I get home. The Yellow tinge is NOT there with the calibration with ChromaPure, but ever so slightly now, a faint twinge of Red but have not quite finished the Grayscale. Will know the results a little later. So far have the Gamma at 2.22 and close to the 6500 +/- throughout. Will let the settings settle and fine tune tomorrow.

Good. Let us know if we can answer any further questions.

The averages were good for Gamma - 2.22
Very good for CCT - 6489
But where do I stand with the CIE94 equalling 0.6?
Is it good, have to go up or down or sideways?

No Yellow - picture seems fuller, and the blacks are definitely better. Still only skirting around the edges of the ChromaPure, but like Catmother says, easier for us beginners to utilize. Calman complete calibration time hours - ChromaPure, in around 1.5 hours without the arm wrestling to get to the final results!

E-mailed Spectracal about the Yellow tinge when calibrating with Calman but have yet to receive a reply back as to some other option having to be set other than the DeltaE being set to 2.22 and the Formula being set to 1996 Standard.

I am going to sound really dumb, but I still fail to see how I tweak the settings my HDTV offers in order to achieve proper calibration.

Nothing specific to ChromaPure.

With all that calibration witchcraft, it's very hard to figure out what to actually do during a calibration session.

p5browne purchased his Chroma 5 from Spectracal with the LED coefficients programmed in and has used the correspondingly modified CalMan, is it possible that could be causing his problems ?.

Since he is now using ChromaPure which ignores those coefficients he seems to be getting better results.

Admittedly a wild guess, but the fellow who calibrate my 55LH90 last October has emailed me with serious complaints about that Calman version.

Sort of caught my eye but didn't register to this morning. With all the IRE values Zeroed - Calman and ChromaPure are reporting different beginning results as to where 100% White is at on the RGB and Grayscale screens. This could be why as I merge the Red, Green and Blue on the Calman software, my 100% White screen slowly tinges to Yellow, and the ChromaPure slowly tinges to Red. Doing further investigation into this and will report on the differences on first initializing both.
One note - on initializing - Calman shows the Blue component way off the RGB 100 and Gamma 2.22 points - the Red closer, versus ChromaPure where it's the Red component way off the RGP and Gamma points and the Blue is closer. (Will give specific values once I warm up the LG tonight and take the readings. A further Note: 90IRE is the worst point with Calman - didn't pay attention when I did the Chroma Pure. Will pay attention tonight.)

I don't remember if you mentioned it in one of your earlier posts, but in comparing reported RGB levels, you should ensure that both software packages are set to the same colorspace, such as Rec. 709. If they aren't, the RGB levels will be different, because they are computed using a matrix based on the standard primaries set forth for each colorspace. I suggest that you instead compare the CIE x and y coordinates that each software package is reporting, as these are not based on colorspace settings but tell you what the meter is seeing. If x and y at each 10%/IRE point are within .001 or .002 with each package (say x=.311 and y=.324 with one package at 90IRE , and x=.310 and y=.325 at 90IRE with the other), then they are likely within the limits of meter repeatability. So the differences you're seeing could be due as much to differences in program settings, session-to-session meter repeatability, and display repeatability as to any functional differences in the programs themselves.

Absent reports it's all idle speculation. The situation is easily remedied. Start a new thread and post complete reports with set-up options from both products.

ChromaPure is on CIE94 all IRE Values at Zero
100 IRE - x=0.299 y=0.307 Y=270.375 RGB Blu= 110 Red= 98 Green= 99
90 IRE - x=0.296 y=0.307 Y=214.177 Blu= 120 Red= 93 Green= 100
Gamma- At 90IRE= 2.1

Calman using D65, HD Rec 709 Gamma Target - 2.22 Formula DeltaE - 1994
100 IRE - x=0.3002 y=0.3005 Y=93.9174 RGB Blu= 115 Red=95 Green= 88
90 IRE - x=0.2982 y=0.3002 Y=74.1364 Blu= 117 Red=94 Green= 89
Gamma at 90IRE and 100IRE - Blu - Off bottom of scale
100IRE - Red=2.4 Green=2.0 90IRE - Red=2.1 Green=2.5

The only Big differences I see is the Value of Y - ie: Y=214.177 verus =74.136 and the Blue at 90 and 100IRE

This was my report on that situation:
http://www.avsforum.com/avs-vb/showp...postcount=2078

This has been reported to Spectracal in a reply to an email from deriksmith along with emails from Bill Hergonson of www.coastcalibration.com