Question about color temps and "correct" looking whites - Page 2

I vote for no more discussion of vision issues and how they affect people... the topic here is CalMAN version 5, let's please keep the discussion to that topic... post a link to the other thread about eye problems affecting vision... in my experience as a calibrator, it hasn't been a factor AT ALL in any calibrations I've done for customers from 75 years old and younger and it's not something that has anything to do with CalMAN version 5... so... gp to the other thread for those eye-related conversations pls?

Doug. The originating post is not about calman. Please read it. If you have trouble understanding the subject, please call me and I will be glad to explain it to you. Better yet. Report me to a moderator. Maybe they will ban me.

I have done calibrations since the early days of CRTs and understand about calibrating to a standard. And calibrating displays to match each other where each display must be the same as in the various computer screens Pixar uses. They have to match. But I strongly suggest you go back to square one to the days of 1931 and the establishment of the chart. The entire calibration system is premised on how colors look to a defined standard observer. Why are movies made with or to a color standard. The premise is the colors are part of the art and they should look the same to the standard viewer. I thinkthe artist like me until recently have or had no clue about the yellowing of eyes with old age. Did you? Its OK. You can answer that question honestly. We are friends here. Speak right up. I won't vote you down. No I think if they thought about it, the artists would understand that not all will see the colors as the standard would intend that they do. A casualty of war. To bad, those viewers just won't get the full deal. But they could, at least in the context of a display if it could be calibrated to offset their color shift. The case where catarcts hace caused yellowing but not blurred deteriarated version justifying the risk of blindness associated with catarc removal and inter ocular lens insertion.i

In all my years, I have never had anybody complain about this either. But let me point it out to you, I never even thought about it before or was cognizant of it. I and I suspect the vast majority of HT customers never thought about it. Yes Doug and Mark. Thank you for making the colors the way the artists intended me to see them. Thank you. Thank You.

But recently it came up for me and a customer friend who had the exact same scenario as me. One new lens and one old cateracted yellow lens. He realized how badly he saw colors for years. and he bitched and bitched and bitched to his eye doctor until the doctor couldn't stand it any more and despite the risks, gave him a new lens for the yellowed eye..

You and Joel need to go back to the standard. You need to examine what people want out of a calibration. Not necessarily what they get. They want to see the colors the way the artists intended. And a medical solution because of the risks of any medica intervention may not be worth the risk.

I am not criticising calibrators. I am pointing out that the average customer with non standard eyes probably will not get what he thinks he is paying for. T the art and science of calibration is reaching a point of stagnation. Probes are cheap, external SMS are available, and automation can and is impacting on the income of many calibrators. The last thing they need is me here pointing out what a calibration doesn't give you if you are older..

The art and science will indeed evolve so that age and yellowing can and is taken into account.
Edited by mark haflich - 2/20/13 at 1:01pm

Oops --- forgot what thread I was posting in... still... there is a thread for vision issues and it would be nice for that not to boil over into this thread also... or to other calibration related threads.

It would be wrong to calibrate a TV to correct for an eyesight abnormality. Why not go as far as calibrating the sunlight so it has more blue?

Also, no one will ever get to see exactly what the director sees on their monitor, as it is more than likely their monitor is incorrectly calibrated.

However, calibration is mainly used to maintain some sort of standards.

Once again, most HT owners get calibrations because they want to see the colors as the artistic production team intended. If a set could be adjusted to do that, then calibrating that users set to do that from him would not be wrong. It would be right. One must assune color production work is done in the correct viewing environment on calibrated displays. If it is possible to take into account visual abnormlities of the viewer, it would not be wrong to do that.

Doug. You are forgiven my friend.

1) So following your premise, what should actual movie theaters do? ... Given that actual film prints seem to be going the way of the dodo ...

2) How do you account (calibrate) for more than one viewer?

3) How would you account for more than one viewer in a theater that still uses film prints?


Just asking I think you may be proceeding from a misinterpretation of what calibration is supposed to do.

And is the calibrator unit calibrated? If so, who calibrates the calibrator? Then who calibrates the calibrator who calibrates that? and so on and so forth.

It should be.

We calibrate meters to our Konica Minolta CS-2000 reference grade spectrometer.
We send our Minolta in every year to get Calibrated by Konica.
They use reference lamps and integrating spheres that use extremely precise physical characteristics to produce a reference spectral output and calibrate off that. Those lamps are produced in labs that are NIST certified.

If manufacturing tolerances are tight enough, then you start dealing with pure materials, you can then rely on the physics of materials. Exciting a pure tungsten (remember tungsten is an element not a compound) with a precise voltage, in a vacuum at a controlled temperature is going create exactly the same spectrum every time.

Who calibrates the voltage and the temperature meters then

Each piece of equipment up the chain is calibrated to a higher traceable standard. This is common knowledge in all industries that rely on calibrated equipment.

Coming from 34 years at the worlds largest imaging company... forget your worrying about who calibrates the calibration gear... there are highly defined and highly accurate reference sources for EVERYTHING.

What you are worrying about is similar to someone worrying about TIME... who knows what time it really is? How does your watch get calibrated? Who calibrates the standard for the device used to calibrate your watch? It all traces back to an atomic clock that is so precise, it is used as the world standard for time. Calibration sources can tap the atomic clock with high degrees of precision.

Same thing for the precise length of a foot or meter or the volume in a quart or liter... there are standards for everything. And each level deeper you go, the more elaborate and scientifically precise the next reference level will be.

There are standards labs for everything that is scientifically or technologically important. At some point in the life of a $10 tape measure you purchase at Home Depot, SOMEONE applied a standard unit of measure to be able to produce the (relatively) accurate markings on the tape measure. The world would be caos without standards.

These labs constantly study how to maintain and improve upon standards used in the past... they do nothing else... just maintain standards for most everything we do in the physical world. n many cases, the standards labs are duplicated in a number of locations around the world so there's always a backup if there's a catastrophy at one location. At some point in the life of every technology, the standards required to create the device in question go back to one or more of these standards labs. NIST is one of the primary providers of standards for a wide range of physical properties... National Institute of Standards & Technology is the primary source of standards for the types of measurements we do for TV calibration. They can create a reference target, for example, measuring many samples and discarding the ones that deviate too much. I've personally seen a production run of 100 pieces of a material used as a standard white reference get reduced to 4 samples usable as references by measuring each one and discarding the samples that deviated too much from the standard reference criteria. Sometimes you overwhelm variables with volume, selecting only the best of the best as references. Other times you use something with extreme high precision (like the atomic clock) as a reference to create a single reference that will be precise without having to make 100 of them and dumping 96% of them... it all depends on your budget, accuracy requirements, and how expensive the methods of producing the samples are.

What we need is a calibration standard for posts. Then we could devise a system similar to calculation of des so we could determine how far a post deviated from the standard and then once a de level to be yet specified the poster would have to be recalibrated in a AVS certified lab.

I do fully understand what a calibration is. Absolutely.

My thesis is that many many in the HT world get a calibration because they think the picture will be better and they will see the colors as the artistic chain intended.

They do not get calibrations for the reasons production houses etc want each display to be the same,


Fortunately, most have good eyes and a calibration will do what they are seeking. but for many it will not.

Obviously, in a multiseat theater one could not calibrate for one set of screwed up eyes without making things wrong for the other viewers in the room with good eyes.

When I watched skyfall two nights ago with my wife I switched to the metered rec709 settings. On the money for my wife but yellowed for me.

But when I watched the basketball games last night, by myself, I switched to my offset calibration, which cranks in some blue gain.

The concept is simple here and even the most oblique calibrator should be able to understand that sometimes only one person is in the theater and things can be made better for that person. Maybe you can't do it or don't want to do it because you must relie on your meters and programs and be able to print out nice graphs showing your customer what he got for his money. Me. I have done that lots of time.

But with littlework, I devised a method for dealing with my combination good eye bad eye vision re color and made it better. Relatively easy because my good eye provides a reference for making the two eye combination vision matvch. No meters. No graphs. Calm down. Don't fall off your chair. In the old days before eters will used optical comparators. The ISF boys sold one. Yep. For setting gray scale temperature and if you were good, like me, it would get you to within a de of 3.

Lots of people have called me recently, all with one cataract removed and living with the other and boy do they bitch about the color difference between their eyes although they see something in between. They bitch because they now know how wrong they were seeing it before with two yellowed eyes and now with one clear and one yellow. I am not alone and there is a fix and yes its a calibration. You start by calibrating to your slave, your master, the thing that makes you great, your meter asnd then you put it aside. You say I don't care, now I will make it look more correct for your eyes. And you let the customer with his ref eye be the meter or rather the optical comparator. And thank you. He doesn't need the graphs, the print outs. All you need is his check.

I would say it's your personal choice. If you like to see the world as it use to be. However, it will not ensure that you see the production as intended, as you have no scientific way of knowing how much out your eyes are seeing the white temp.

In this respect you would have to adjust to your personal tastes. If I had errors in my visual system I would still prefer the calibrated option, as it would provide a window of what I see in the real world.

Apologies for the wording of this mail. It isn't easy compiling a mail on a phone

The concept may be simple, but the execution is not.

1) To do what you want, you'd need to be able to accurately measure the response of your eye(s.)

2) In your specific case there's no easy way to "even out" the response between your eyes by "calibrating" a display. Either you need to go with some type of VR glasses that can hold different "calibrations" for each eye, or perhaps you could build a box that turns a 3D capable display into one that flashes different "calibrations" for each eye (instead of depth content.)

But even if you manage to accomplish the task(s) laid forth in point 2, you still have no guarantee that you are going to see the "same" colors that the colorist saw when he/she mastered the program material. (Neither does anyone else ... because there's no way to know the response of the colorist's eyesight.)

PS: I'm convinced that the master engineer at one of my local TV stations was cranking up the blues back in the analog days due to his suffering from your former condition.
Edited by HDTVChallenged - 2/21/13 at 12:20am

Have one eye with essentially no filter, I van switch to the ref by the book calibration and then switch to my ad hoc custom calibration with both eyes open to duplicate the ref from my good eye. even if it is off, the net result with both eyes is clearly closer to the truth than just stcking with the right eye ref and skewing it towars yellow by both eyes combining. Sometimes your eyes can do a better job than the meter, really.

Yes ... but the point is that you have no way of knowing that if *both* of your eyes are "yellowed" ... You had no idea how "bad" your eyesight had gotten until after you had one lens replaced.

You still seem to be trying to blame your display/calibration (if not the whole concept of display calibration) for a fault that clearly lies elsewhere.

You have a legitimate issue, you're just looking for a solution in the wrong place(s.) It would probably be quicker and cheaper to experiment with blue filters over your "yellowed eye," or better yet just wear an eyepatch over the offending eye .... ahrrrrggg.

Why is it everything on here lately is about yellow catarac's? Getting so incredible boring to read about and it ruin every good thread. Leave it in this thread please...

ahh feel so much better now

All he needs to do is pull out his eyes, wire the optic nerve to a meter, then point the eye to a light source. Run through the tests, then his eye would be calibrated. Use these to then calibrate his TV so once the light goes through his eye, it will be correct.

Of course each eye would be different so you'll need to do this twice, and have two TV's.

I'd be happy to ... OTOH, bad ideas (even if a bit off topic) need to be countered if and when they crop up in "the good threads," otherwise they continue to metastasize and the next thing you know you've got a legion of golden-eyed videophiles talking nonsense about clarity, forwardness, ambiance, openness, 'refined color palates with just a hint of nutmeg overtone ..." etc, etc ...

PS: To keep my blood pressure under control, my imaginary doctor has "advised" me to avoid the audio sections of this forum.
Edited by HDTVChallenged - 2/23/13 at 10:28am

non the less if this keep going on I fear it will end up with people avoiding this part of the forum. No I dont think that will happen but since the legion is still a one man army, could we not kill it by silence I will back off for now and leave it, with a plea of keeping this topic to its own thread.

I have recently spent considerable time with people from production houses and there a much more intune with there being too much of a big deal in calibrating displays. the system is flawed except for making multiple displays all performing the same. many use multiple monitors on their desks and simple do not want to see the colors change between displays. as to seeing what the colorist sees, they laugh because many colorists are of advancing enough age to have yellow filtered eyes.

the HT consumers generally could care less about matching his various displays. He wants to see the colors as the artistic chain intends them to be seen and that is flawed.

W e sell the consumer on that though.

But it is all BS. The coordinates are based on a multiplier chosen for a defined standard viewer. Colorists (man) and HT consumers (many) do not have eyes meeting that definition.Unless one eye has been corrected with a new lens there really is no way of making a two eyes summed correction because there is no way of measuring the degree of filteration where both ares have yellow filters due to aging.

But I do feel that for many investing in equipment and programs to calibrations or even paying for a calibrator which essentially be almost a complete waste iof money. They will simply not get the objective they are seeking.

And the argument of calibrating to see it the same as you would see it in real life is specious. You have the error introduced by the colorist's eyes and the fact that viewing outdoors etc will ralely be under the same lighting conditions the film was shot. Its all BS.i

There has never been a man made system that hasn't been flawed. With all the enormous devotion of talent and funding to NASA over the decades, they still lost one capsule crew and two shuttle crews. There has also never been a time when a certain portion of video program professionals haven't argued and fought against the implementation of standards, engineering guidelines, and recommended practices published by industry standards bodies. It gets even worse in the consumer electronics portion of the video industry. Industry professionals can have all sorts of agendas, based upon a wide variety of motives. Standards bodies like SMPTE and the ITU are faced with a daunting challenge to unify and elevate the international motion imaging industry. THX faced similar opposition in their original mission to promote the observance of SMPTE standards and best practices in the film mastering and exhibition segments of the industry. Their task has to be reminiscent of the proverbial herding of cats. Genuine leaders and luminaries in the industry are tireless advocates of unity, consistency, reliability, quality, fidelity, and discovery. However, as with any field of endeavor, there will sometimes be loud voices that get attention, only to advance an ego, a misplaced sense of priority, or obsessive-compulsive cynicism, etc. There is room in any industry for disagreement and debate. How does any side of an argument elevate the subject, not just propose a contrary perspective?

Here's a testimony from an award winning expert from within the cinematography ranks that sheds light upon this discussion:

"2 April 2008

From Allen Daviau, ASC [ http://www.imdb.com/name/nm0005679/ ]

Today's cinematographers go to great lengths to insure that all of the richness, range, and detail of their original images reach the home screens of the viewers. Throughout the photo-chemical laboratory processes and the full range of digital manipulations, the cinematographer who cares wants to ensure that every step taken is in the best interest of the look of that motion picture.

This has been the case for some time, but with the real arrival of a High Definition television system and the subsequent enlargement of the home image size, the responsibility has a greater intensity. We, and all of the technicians who work with us, want you to feel all of the power of those images that so many people, in front of and behind the camera, fought to achieve.

I think that you would be very pleased with the intensity and precision of our efforts. In return, we make an important request of you. Please be very sure that your home viewing screen is capable of displaying all of the quality that has gone into the motion picture that you are viewing. You may own a very high quality system, but if it has not been properly calibrated, you would be shocked at how much you are missing.

Starting with the quality of your incoming signal, be it from an antenna, cable, satellite dish, or disc, it should be capable of delivering everything in the original master. The adjustment of your display device should be done to insure that it is accurate in terms of contrast, brightness, color temperature, and color intensity.

Unfortunately, the manner in which displays are adjusted at the factory is to ensure that it gets attention in a store, surrounded by many other screens. It has not been adjusted to display the qualities that the filmmakers considered important. If you have these adjustments made properly, your enjoyment of those images will greatly increase. You will be seeing what we intended you to see, and all of us, the creators and the audience, will be very much happier.

It is well worth your time to be certain of your investment."

Electronic motion imaging excellence is a fairly complex subject. Discussion must include the behavior of the electrical signals, functions of the recording and delivery devices, and human factors. One great key to not getting misdirected in such discussions is to not lose sight of the fundamentals. It may be helpful for readers to review this link: 'Display Calibration: Root Fundamentals'

It should also be acknowledged that there are more parts of the body that deteriorate with age than just the eyes, and affect one's powers of perception. Eyes can be physically intact but the optical cortex in the brain can suffer diminished function or damage. The brain also can suffer from senility and Alzheimer's at surprisingly young ages. Memory, perception, cognitive reasoning, and comprehension start to suffer. Much depends on genetics, diet, and lifestyle. Case studies are not comprehensive or complete due to the many sufferers who go unrecognized and/or unreported.

Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
A Lion AV Consultants affiliate

"Advancing the art and science of electronic imaging"
Edited by GeorgeAB - 2/28/13 at 2:12pm

A very nice post george and well balanced,

Of course can';t even get the wider DCI color gamut not a high enough bit rate to vanguish banding or present the many more specific colors that any one space could produce.

i am not arguing about standards but I do argue because the color standards are defined and calculated based on a defined standard viewer, they are necessarily flawed. Something I have forgotten over the years and the fact that because of aging and other things one might not see the colors the artistic chain might want you to see.

Moreover, i have become critical of misleading customers (the whole system not necessarilly an individual calibrator), into thinking that you will see those intended colors with a calibration. Of course a decent calibrator in his calibration process can make the picture bettter than just color fidelity wise.

i think you know me better than to say I am operating for my ego etc here. I don't think you were aiming those comments at me.

i think my points are valid and should be fleshed out and recognized instead of being quashed. They are valid concerns by an industry professional with impeccable credentials including ISF certification.

In a few years we will indeed have much larger color spaces and longer bit length.

As to older folks I will be vigilant in expessing my views that calibration may not give them what they might otherwise expect.

As to colorists, they probably have no clue as to the accuracy as to how they see colors. I never knew my color perception was so wrong until I got a new lens. Then wow. Detrioration is gradual and one just thinks nothing has changed.

Once again thank you for your post. it has added to this discussion with a level of maturity far exceeding mine,

Talking about other things changing with age, I would proffer the various reactions one might get while watching a porn flick at 25 vs 65.

Mark, are you getting grumpy? Are you becoming a dogmatic iconoclast?

I think we all get what you are saying, agree with the premise, but don't find it that useful in moving forward.

You sound defeated... like because the system we have now isn't perfect, we should just forget about it.

I'm not there yet even though I'm old enough to get social security and I don't see switching to the (your) Dark Side of the force any time in the forseeable future.

I didn't say that.

i am saying that our system doesn't deliver what some are attempting to get.from it. The colors looking to you the wat the artists intended.the

And this thread is about getting correcting looking whites. The key word is looking which implies correct looking to you. We say we will justy adjust as to how they should be if they meet the standartd. But no guarantee that you will see them correctly for a varieTy of reasons. And if they don't look right to you but measure right, then chage them you can accomodate and deal with change and the factors which necessitate change, calibratrors obviously wear blinders. it measures right, yoiu are wrong.

And never let a calibrator tell you something is the correct gamma. There is no such thing for a HT display.

That's exactly what our system does.

It attempts to reproduce the colors the colorist saw (I didn't say perceived) as accurately as possible. Perception is a can of worms, that is beyond the control of a calibrator and is not something they are trained to understand. Nor is it a topic even the most brilliant minds in color science believe they understand well enough to produce reliable models for.

Calibration seeks to make your display produce the same colors the colorists display produces. It does that exactly that within visible tolerances.

Once again you refuse to address that the marketing of HT calibration has left Joe consuner into inappropriately thinking he will see the colors on his display the way they are perceived by those in the production chain perceive them and that sinply is not the case. Second, calibrators sell gamma calibrations at 2.2 or 2.22 as if it were some sort of standard to be met, leaving most customers with a straight line gamma of 2.2 or rather a perfect 2.22 curve is a travistry. It should be done by showing the customers various gammas including curves to see what the customer prefers rather than misleading through the calibrator's ignorance perhaps or the customer's that there is a display gamma standard.
Edited by mark haflich - 3/2/13 at 5:31pm

travisty? That's pure hyperbole.

The difference between 2.2 and 2.3 is subtle, and is the range most content is mastered at. Also if a room has ambient light, it's incredibly appropriate.

CalMAN ships with the default of 2.2 for a reason.

That's not remotely true, and the fact that you would say that demonstrates you're out of your depth discussing this topic.
Edited by sotti - 3/1/13 at 8:04pm

Joel. I have edited my post to clarify what I was trying to say.

I have no problem with setting a default in your program of 2.2.

Nothing makes that much difference, does it?

Turn it up at the low end by eye if the meter sold by you and others is not accurate enough to measure the low end accurately; Of course, there is good value in the consumer probes sold by Spectracal and others. Those meters are not true reference professional probes but they are more than adequate for non professional use and except at the very low end of the gray scales they are of great use to all including professionals because of their great speed if they are calibrated on site against a reference quality instrument.

I am sorry if you feel I am out of my depth. I guess I wouldn't be if I owned or worked for a calibration program company including one that sold equiipment. And of course I would never be biased. Everyone then should accept what I say. And if I get angry or annoyed in a post no one should feel that maybe there is a kernal of truth in the post I got angry about. Spectracal is a very very calculating company and has good reasons for everything it does and consuners should be blessed that their (the consumers') interest come first.

Seriously, Spectracal makes and sells fine products and is responsible making calibration more affordable and easier to do for all.And it has advaced the art and much of that is due to you.

.

No one alive is unbiased! How insulting! Even if said un-seriously, or in jest, such a comment is in very poor taste. Attempting to cover for it by following with a compliment only sounds schizophrenic. Joel is one of the most capable contributors to this area of the forum, and I am confident there are very many members of this forum who have only gratitude for the time he devotes to elevating the discussions here.

There used to be a time when representatives of manufacturers were very welcomed and encouraged to participate in this forum. It should be obvious to any sound thinking, mature, forum member that comments from someone affiliated with a manufacturer or provider of professional services would have a bias in favor of said company. Unfortunately, there has developed in segments of our culture an undercurrent of resentment, suspicion, and cynicism toward businesses and their representatives. This poisonous presumption ignores the reality that the majority of businesses only endure/succeed by offering products and services that benefit consumers. "Profit" is a bad word or concept in the minds of the ignorant and immature. In truth, it is the result of fair exchange. Without it, providers of products and services cease to exist and employees are without a paying job. The technologies at the root of this entire forum would not exist without private property rights, profit making companies, our free market capitalist system, and representatives of those companies advertising and promoting the goods and services they provide to consumers. "Goods and services"- interesting terminology, eh?

Gratitude is a virtue in increasingly short supply in today's culture. Proficient, experienced professionals and technical experts keep this forum from devolving into a mass of misinformation and confusion. Are they typically biased toward their professions and devoted to their companies and employers? They had better be! Are they passionate about the advancement of audio and video science and practical solutions? Invariably! Should consumers resent the fact that they make a living from such devotion? Only if they are a fool.

Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
A Lion AV Consultants affiliate

"Advancing the art and science of electronic imaging"
Edited by GeorgeAB - 3/5/13 at 10:12pm