Can one "calibrate" to a different color standard than D65? - Page 2 - AVS Forum
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post #31 of 97 Old 08-20-2009, 07:37 PM
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To answer the OP, in the menus Advance-> Preferences, go to the references tab, and you can change the white point from D65 to a number of other points... not that I advise it. I prefer an accurate image... but...
I think it's poor practice to say if someone doesn't care about accuracy they don't care about quality. I happen to care about both. But... and I know this has been gone over elsewhere many times, but... Accuracy is scientifically measureable, and that makes it objective. Quality on the other hand, in this case at least, is not. It is therefore subjective, and therefore in the eye of the beholder. It is entirely possible for one to view inaccurate images, to like them more than accurate images, and in their eyes they then have better quality. For some of us, the two are inseparable, but to force that opinion down someone's throat is parochial, and actually hurts our cause...
For the record, this is the best advice the OP has gotten in this thread so far:
Quote:
Originally Posted by andrewfee View Post

D65 is already a slightly blueish whiteit's just that we're so used to the defaults being much higher than that, it looks reddish at first.

I'd give it some timeonce you've watched enough D65 content, higher colour temperatures will start to look worse, rather than better.

And this is the funniest:
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Originally Posted by GeorgeAB View Post

SOWMK....someone who might know?

And this is the truest:
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Coincidentally, our current culture is a hell of a lot more rude than it used to be.


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post #32 of 97 Old 07-17-2013, 10:08 PM
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Originally Posted by GeorgeAB View Post

Are you Japanese? They use a much higher white point for their broadcast standard. The rest of the world uses D65 for video white.
I prefer the Japanese preference for a high-contrast image.
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Originally Posted by darinp2 View Post

If he meant "contrast" as in ANSI lumens then those can be increased by going to a higher color temperature with many displays also.


I'm not saying he should do it, but one thing going to D65 often means is getting less than maximum contrast ratio.


--Darin
Which is why it's preferable to go the Japanese route.
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post #33 of 97 Old 07-17-2013, 10:10 PM
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Originally Posted by TomHuffman View Post

Lastly, there have been some studies that suggest that many people mistakenly perceive a bluish white as "more" white. This is precisely the bias that people concerned with image fidelity have tried to fight through education and calibration to correct standards.
They're not mistaken--colors on a video display are artificial regardless of how natural technicians attempt to make them appear--our eyes are drawn to a higher contrast image.
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post #34 of 97 Old 07-17-2013, 11:13 PM
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And today's award for the most unnecessary revival of a 4 year old thread goes to ...
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post #35 of 97 Old 07-18-2013, 05:26 PM
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a higher color temperature than 6500 gives a more balanced/even grayscale on mine.Otherwise I end up with more red in the dark areas and more blue in the brightest areas so it's not balanced looking.The higher color temperature works better when using a brighter gamma.Samung pne450
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post #36 of 97 Old 07-18-2013, 06:52 PM
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Quote:
Originally Posted by homogenic View Post

I prefer the Japanese preference for a high-contrast image.
Which is why it's preferable to go the Japanese route.

The Japanese don't have a preference for high contrast images. But they do tend to be attracted to images with higher-than-natural saturation as are most people in most countries of the world. That's why Fujichrome outsold Kodachrome and Ektachrome (both more accurate) in Japan. It has been a long time since I read about why Japan uses 9500K on their TVs but it's likely it's because the broadcast standard is 9500K. Not because they like images that are too blue with zombie-like fleshtones.

If you calibrate 1 TV to d95 and display a d95 source on it and place it beside a second identical TV calibrated to d65 displaying the same source but converted to be a d65 source, the 2 images will look the same. The problems come when you display d95 content on a d65 display or vice versa.

Ditto for d75. The programming you are talking about originates as, nominally, d65. There are a TON of variables of course. Daylight versus stadium lighting is one of the HUGE variables. Who knows what the d-point is for stadium lighting? And it's very possible the d-point is different at different stadiums. A cloudy day can be d75 or even more blue that that... d80 or d85 is possible. So are you going to have a different calibration for "sports" to cover clear skies, partly cloudy, overcast, night-time with stadium lighting, dusk with stadium lighting... it's an endless shift that the broadcasters may or may not be compensating for... or they may only partially compensate. Since they are broadcasting nominally at d65, if you view the programming with d75, you will see images that are blue-er than they intended them to be. White will NOT be whiter at d75, it will be blue-er at d75. If you want d65 to look whiter (in the same way d75 would look whiter) just view programming at d55/d54 or even d60 for a while. When you switch to d65, white will look MUCH whiter.

All you are doing by viewing at d75 is succumbing to an optical illusion. White is not whiter at d75, it is more blue. And of course, red will also be more blue, green will be more blue, yellow will be less yellow, cyan will be more blue, So none of the colors any of the players are wearing will be accurate (since the broadcasters are sending nominal d65 video). So if you like your reds, magentas, greens, and cyans made less accurate (by having added blue) and if you like your yellows desaturated and weaker looking, by all means, setup a d75 viewing condition.

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post #37 of 97 Old 07-18-2013, 09:05 PM
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Quote:
Originally Posted by Vic12345 View Post

a higher color temperature than 6500 gives a more balanced/even grayscale on mine.Otherwise I end up with more red in the dark areas and more blue in the brightest areas so it's not balanced looking.The higher color temperature works better when using a brighter gamma.Samung pne450

It is either calibrated incorrectly or that TV is not capable of producing a linear grayscale.

And Doug is dead on. D95 is not a "whiter white", it's a bluer white (along with a bluer everything else and an undersaturated yellow). There is no such thing as a whiter white. White is white.
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post #38 of 97 Old 07-18-2013, 09:52 PM
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"White" is the designation we give a mixture of the three primaries in color perception. The only color of white in video that can be considered neutral is the CIE "E" point, where "equal energy" is provided from the red, green and blue primaries (roughly 5400K; x- 0.333, y- 0.333). The blue tilt in settling on D65 (roughly 6500K; x- 0.313, y- 0.329) as the video white point, comes from the CRT days, when a perceived brighter bluish white helped compensate for the limited light output of the technology.
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post #39 of 97 Old 07-22-2013, 03:06 PM
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Sports stadium lights are super bright,cause abl activity,make the picture cloudy/dim like any bright scene on plasmas I've seen.But the white uniforms remain torch shiny white from the super bright stadium lights.A game at dusk with stadium lights turned on causes problems,as do other scenarios.A plasma thing,although torch whites happen on crts too.

Because abl dims it (reddens it)so much on mine I think it needs too look good when abl is active.samsungpne450.Making sure you don't see much red on black and white in a dark room helps on this tv.While at the same time making sure the blue is high enough.Ends up a higher color temperature.The plasma abl dimming is constantly changing the color temperature.Using a Different color temperature affects how the tv responds too abl/gamma changes..I think a higher color temperature makes the plasma varying temperatures more stable...So when the abl is quite active = worse looking picture.Every different plasma tv model has at least slightly different abl activity.I'm not saying its 100% true,as I'm learning still.
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post #40 of 97 Old 07-23-2013, 11:49 AM
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I've never seen brightness limiting shift "color temperature" and I watch a Samsung plasma all the time. If you are seeing that effect, it is NOT coming from brightness limiting. You are seeing something else entirely... something completely unrelated to brightness limiting. I can measure the Samsung plasma I have here with a very small window size measuring 35 fL then display a full-screen 100% white pattern. The full-screen pattern measures about 17 fL for 100% white but there is no significant color shift compared to the smaller and much brighter window.

I'm not sure what you are seeing or why, but it doesn't have anything to do with brightness limiting.

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post #41 of 97 Old 07-23-2013, 01:03 PM
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Never wrote original settings(as I knew I'd be changing it), but I'm pretty sure out of the box there was a fair bit of color shifting when it went too full screen white.Besides the red/magenta push and other color problems. I've got it close now if the small white window and full screen white are suppose to be close to the same temp..Its been said before that the display may determine the best color temperature too use.Thats the case on mine.

Other thing different with plasma is a brighter room requires a lower contrast setting if you don't have much of a light filter...And I've always found tvs are way easier to adjust for most things at night in a black room,but gamma is easier to adjust in a bright room if you watch it in a bright room.

Edit Other thing I've found is with lower contrast and higher color temperature requires a higher color control setting, otherwise it's too dull.

thanks for da help
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post #42 of 97 Old 07-23-2013, 02:23 PM
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Quote:
Originally Posted by Vic12345 View Post

Never wrote original settings(as I knew I'd be changing it), but I'm pretty sure out of the box there was a fair bit of color shifting when it went too full screen white.Besides the red/magenta push and other color problems. I've got it close now if the small white window and full screen white are suppose to be close to the same temp..Its been said before that the display may determine the best color temperature too use.Thats the case on mine.

Other thing different with plasma is a brighter room requires a lower contrast setting if you don't have much of a light filter...And I've always found tvs are way easier to adjust for most things at night in a black room,but gamma is easier to adjust in a bright room if you watch it in a bright room.

thanks for da help

Vic, I hate to be bluntly honest, but I don't think you actually have any idea what you're doing.

Until you get some hardware and quantify what you are actually doing, your advice is less helpful than simply sharing settings. Your insights are unfounded and not backed up by scientific observation in any real way and in some ways are directly detrimental to the goal of this forum. If you want to play with your settings and talk about how you feel about the picture that is what the display forums are for.

In the calibration forum, we are looking for ways to align the picture to well defined standards. We have given you all the advice we can about setting up the TV without hardware. If you want to continue to participate in this forum, I suggest you go purchase a meter and some software and begin to discover what calibration actually means.

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post #43 of 97 Old 07-23-2013, 03:21 PM
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Quote:
Originally Posted by sotti View Post

Quote:
Originally Posted by Vic12345 View Post

Never wrote original settings(as I knew I'd be changing it), but I'm pretty sure out of the box there was a fair bit of color shifting when it went too full screen white.Besides the red/magenta push and other color problems. I've got it close now if the small white window and full screen white are suppose to be close to the same temp..Its been said before that the display may determine the best color temperature too use.Thats the case on mine.

Other thing different with plasma is a brighter room requires a lower contrast setting if you don't have much of a light filter...And I've always found tvs are way easier to adjust for most things at night in a black room,but gamma is easier to adjust in a bright room if you watch it in a bright room.

thanks for da help

Vic, I hate to be bluntly honest, but I don't think you actually have any idea what you're doing.

Until you get some hardware and quantify what you are actually doing, your advice is less help than simply sharing settings. Your insights are unfounded and not backed up by scientific observation in any real way and some ways are directly detrimental to the goal of this forum. If you want to play with your settings and talk about how you feel about the picture that is what the display forums are for.

In the calibration forum, we are looking for ways to align the picture to well defined standards. We have given you all the advice we can about setting up the TV without hardware. If you want to continue to participate in this forum, I suggest you go purchase a meter and some software and begin to discover what calibration actually means.
Thank you, Joel. I was fast approaching my tolerance threshold for such surreal comments. Sometimes one grows weary of intervening. I'm heartened that there is not a shortage of participants in this section of the forum who make the extra effort to keep the wheels on the rails.

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post #44 of 97 Old 07-24-2013, 12:45 AM
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Ok I was just seeking some help from the guys that do know a bit about it.I haven't found much help for my tv in the owners thread. tongue.gif
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post #45 of 97 Old 07-24-2013, 09:00 AM
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Quote:
Originally Posted by Vic12345 View Post

Ok I was just seeking some help from the guys that do know a bit about it.I haven't found much help for my tv in the owners thread. tongue.gif

And we love to help people calibrate their TV's here. But calibration does not mean the settings that look like they have the most contrast or are the most vivid. Calibration means aligning the display to "A STANDARD", only when your display is calibrated to the same standard as the monitors that were used in production will you see the correct image.

You must understand the things your eye and brain can perceive and the parts of calibration that can only be done with a meter. We are happy to help you align the settings that can be done optically and we can hold your hand if you decide to get a meter. But talking about doing white balance by eye or calibrating to a white point other than D65 is not constructive for this forum.

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post #46 of 97 Old 07-24-2013, 10:52 AM
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Quote:
Originally Posted by Vic12345 View Post

Ok I was just seeking some help from the guys that do know a bit about it.I haven't found much help for my tv in the owners thread. tongue.gif
This and other "sticky" threads from the top of this section of the forum are a good place to start:

'Display Calibration: Root Fundamentals'
http://www.avsforum.com/avs-vb/showthread.php?t=1021933

The vast majority of video consumers have less than a half-vast foundational understanding of even the simplest video basics. Most videophile hobbyist types learn bits and pieces of randomly accumulated information over time, rather than from structured, methodical, disciplined, formal instruction. Many forum members have learned largely from other members. These forums are a mixed bag of good and bad information, from mostly well-meaning but partially informed enthusiasts. Many make assumptions based upon insufficient or faulty information. Confident assertions abound, but often only mislead and misinform readers who have no foundation in imaging science fundamentals, or video industry standards and recommended practices. Much of what is said in the display owner segments of the forum is based primarily on anecdotal observations, opinions, and experiences of consumers. Consumer video product marketing hyperbole is also a culprit.

Video is science in the service of art. There can be no coherent video industry without a disciplined adherence to industry standards and recommended practices. The American video system in the days before digital TV was called NTSC ( referring to the National Television System Committee). For many decades there was not the kind of discipline in the system we see today. There was such chaos that it was cynically referred to as "Never The Same Color." A pivot point was reached when Joe Kane chaired a SMPTE working group studying broadcast monitors in the mid '80s, then was encouraged by the group to promote their findings and recommendations to other professionals, display manufacturers, and consumers. Joe Kane also co-founded the Imaging Science Foundation with the current President, Joel Silver. About that time Joe also produced the first display calibration program on optical disc used by consumers and professionals alike. It was on laserdisc and titled: 'A Video Standard.' The AV Science Forum founders were significantly inspired by these efforts.

Imaging science and display standards became popular topics in the video hobbyist print media of the day. Better informed consumers, with laserdiscs in hand, began confronting TV retailers about the poor performance of their wares, and their TVs not being capable of displaying correct video pictures. TV manufacturers started to improve their products. The ISF began getting traction in their efforts to get display manufacturers to include more features and options for calibrating their equipment properly.

The most readily accessible resource for studying imaging science and display standards, along with how to correctly evaluate and adjust video systems, is the popular tutorial programs available on optical disc. They are a great way to begin a more reliable study of how video and displays actually work. Another good historical resource is available in PDF format from 'Widescreen Review.' Here's a link where you can purchase it: http://shop.widescreenreview.com/products/Imaging-Science-Theatre-2000-%28Digital-Download%29.html .

Only a solid foundation in imaging science fundamentals, plus display industry standards and practices, can prevent false assumptions and misconceptions about how video works, and what displays do. It just takes time and effort to establish an understanding of these fundamentals. Excellence in any endeavor requires extra devotion and persistence. The reward is better pictures. As Joe Kane insists: "It's all about the art."
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post #47 of 97 Old 07-24-2013, 05:27 PM
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Quote:
Originally Posted by homogenic View Post

They're not mistaken--colors on a video display are artificial regardless of how natural technicians attempt to make them appear--our eyes are drawn to a higher contrast image.

Video color is no more "artificial" than color in a photo, color in a movie, color on a refrigerator or washing machine, on a car, on a can of Coke, on clothing, on a page of a magazine, on a house, or even on an apple or orange or tomato or flower or leaf. ALL color excites the rods and cones in our eyes in precisely the same way regardless of origin.

Every current imaging technology has gamut and contrast limitations... video, printed page, film, digital video cameras. None of them fully duplicate the live viewing experience with total precision, but they can be so close to the live viewing experience that you essentially replicate (closely, if not precisely) the live viewing experience.

Your statement regarding people being drawn to a "higher contrast image" is SCIENTIFICALLY proven to not be true. You seem to be equating high contrast with color temperature and they have nothing to do with each other. A 9500K image will have PRECISELY the same contrast ratio as a 6500K version of the same image provided your viewing medium (film, digital display, printed page, etc.) are the same for both images and that the images are not manipulated beyond changing the color temperature.

If you have a test subject and show them 2 photos of, say, a bowl of fruit and flowers on a wood table partially covered with an interesting textile, given no instruction nor any reference image, they would have a tendency to pick an image that was slightly more saturated. But if you provide the test subjects with a REFERENCE, like the original scene with the original lighting and they can then compare the 2 images to the reference. If you then instruct the test subjects to select the most accurate representation of the real "scene" they actually do quite well at selecting the more accurate of 2 (or more) test images.

We have a reference standard for video. When the source adheres to the standard, and the video display adheres closely to the standard, you get a surprisingly good match for the original, a match made possible by engineers and technicians from many disciplines working with the same standards. The thing about video is that if you get video images around 80% accurate or better within the capabilities of the video display technology, the human brain begins to accept them as real and you will get physical responses to impending danger (combat simulation, flight simulation, race car driving simulation, and TONS of video games). Even when the test subjects KNOW they are in a simulation, they can't stop the physical responses to what is happening in their video environment, even though it may be 100% artificial in the sense that it only exists in video. And that alone keeps the video game industry pushing the envelope to make gaming experiences increasingly more intense.

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post #48 of 97 Old 07-28-2013, 06:59 AM
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Quote:
Originally Posted by Doug Blackburn View Post

Your statement regarding people being drawn to a "higher contrast image" is SCIENTIFICALLY proven to not be true. You seem to be equating high contrast with color temperature and they have nothing to do with each other. A 9500K image will have PRECISELY the same contrast ratio as a 6500K version of the same image provided your viewing medium (film, digital display, printed page, etc.) are the same for both images and that the images are not manipulated beyond changing the color temperature.
Would you provide a link to at least one study that validates this?
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post #49 of 97 Old 07-28-2013, 10:35 AM
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Greetings

Two TVs ... both outputting an image at 50 fL ...

One TV has a black level measured at 0.05 fL ... Contrast ratio .... 50/0.05 = 1000. 1000:1


The other TV has a black level measured at 0.005 fL ... Contrast ratio ... 50/0.005 = 10000. 10000:1


People are not drawn to the TV with the higher contrast image. in a room. They are both equally bright.


In that same vein, add one more TV ... 100 fL ... but it has a black measured at ...0.1 fL ... 100/0.1 = 1000. 1000 :1 CR

This is the TV that attracts people in the room ... it is brighter ... but it clearly has a CR lower than the set that can do 10000:1

Same reason why LED/LCD sets on showroom floors are brighter than Plasma sets and attract people, but the plasma sets have greater contrast ratios.

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post #50 of 97 Old 07-28-2013, 12:07 PM
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Quote:
Originally Posted by homogenic View Post

Quote:
Originally Posted by Doug Blackburn View Post

Your statement regarding people being drawn to a "higher contrast image" is SCIENTIFICALLY proven to not be true. You seem to be equating high contrast with color temperature and they have nothing to do with each other. A 9500K image will have PRECISELY the same contrast ratio as a 6500K version of the same image provided your viewing medium (film, digital display, printed page, etc.) are the same for both images and that the images are not manipulated beyond changing the color temperature.
Would you provide a link to at least one study that validates this?
Doug's statement bugged me, too. Perhaps he's referring to program content contrast in the extreme. Comparing two displays of equal brightness, with one being of higher contrast, the average viewer will typically prefer the higher contrast image (all other factors being equal). Here is a quote that relates to this issue:

"Contrast could be considered to be the most significant quality that impacts not only the perceived depth of an image, but also affects the apparent sharpness.

Contrast Defined

The term contrast is used universally to describe differences between luminance levels of any given image. Typically for video products, contrast describes the performance of any given image in terms of its luminance at black relative to its luminance at white. Fundamentally, the relative difference between the two levels is expressed as contrast ratio. The term contrast alone is defined as the difference of the two luminance levels divided by the sum of them."

'SMPTE Journal' Issue: November 11, 2002: 'The Importance of Contrast and its Effect on Image Quality'; By: Segler, Pettitt, and Kessel

"Access to past issues of the journal from 1916 to current is available in digital form.

Access rights vary depending on SMPTE membership. For SMPTE Members (Except Associate Members): Unlimited access to all journal content. For Non-members: Purchase any article on a pay-per-view basis for $20/document.

If you have questions, please contact Dianne Purrier at: https://www.smpte.org/smpte/71578/contact "
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post #51 of 97 Old 07-28-2013, 05:18 PM
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I was interpreting the statement to mean NOT that the black level or white level in the images was different - that would make it damn near impossible to make any qualitative judgements about the images... you have to have some standard "set points" in the image in order for any comparisons to be valid. I've been considering contast in terms of the difference between light and dark that you get with different gamma curves... low gamma (numerically) reduces differences between shadow and highlight (lower contrast) while higher gamma increases differences between shadow and highlights. You can vary this without changing the black point and white point. Obviously EVERYBODY (not just Japanese or Asian) will appreciate an image that has blacker blacks than a milky black version of the same image. And, equally true, EVERYBODY will appreciate an image with bright crisp white compared to a duller version of the same image so you can't base any legitimate comparisons on that.

My comments come from 34 years of working on imaging systems for Kodak, often with image scientists who either directly conduct image preference studies or benefitted from studies done by image scientists working in other areas (Kodak, at it's peak, had phenomenal image science resources that I benefitted from often, and every program I ever worked on had dedicated image scientists assigned to both the product development cycle and to product support after the product was released (these were professional imaging products for a wide variety of markets, not consumer products which also had a ton of image science support). And no, I can't give you any links to this information because it was not published publically.

You put an image with milky blacks and dull whites next to the same image with black blacks and bright whites and there's nobody anywhere who would prefer the crap version of the image. It did not occur to me that anyone would ever even consider that kind of comparison that would have such an obvious outcome. It's like asking if you prefer breathing or not breathing, eating or not eating, etc.

When it comes to evaluating images, there was a TON of work done on the linearity of film and photographic paper and ink jet printer output (high-end printers). None of it focused on "contrast" (i.e. black point and white point) as those points were fixed by the technology and were not adjustable, nor would you want them to be. If you wanted low contrast images you could simply adjust the source so that black was at 5% white instead of 0% white or whatever. So when evaluating images and image preference, the discussion was always around how linear the response of the film, paper, ink, camera, scanner, projector or whatever was between shadows and highlights... which is essentially gamma... the systems ALWAYS allowed you to "adjust" that parameter within the confines of your technology constrained black and white points. Putting a dip or bulge in the luminance curve (versus the linear, 45 degree line) makes images look less or more contrasty without actually changing the white point or black point.

With that background in mind, it simply never occurred to me that black point and white point were the intent of the statement. Based on the research I saw and used, blacker black and whiter white was a UNIVERSAL preference, not limited to ANY ethnicity. But there were ethnic preferences and the Japanese in particular, in the photographic realm, had and continue to have a preference for color that is slightly more saturated than the original image --- unless you present them with the original subject and ask them "which photo looks most like the subject"? In THAT case, they, like every other ethnicity tested would consistently choose the image that really was most like the original. But when the focus was on family photos, vacation photos, party photos and such, everything else being equal, they would prefer a bit more saturation than the original scene contained even when they were in the photos (and obviously at the event in question and knew the actual real-life appearance of the event). I never saw ANY studies where ANYONE wanted to see less black blacks or duller whites in their images that any other ethnicity.

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post #52 of 97 Old 07-28-2013, 06:16 PM
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I think the point here as Doug mentioned earlier was that higher color temperatures don't produce a higher contrast image than that of a display properly calibrated to D65, since color temperature and contrast ratio are not related. So, 'higher contrast image' was just referring to what other poster was talking about (higher color temperature image to be exact).


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post #53 of 97 Old 07-29-2013, 03:38 AM
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This and other "sticky" threads from the top of this section of the forum are a good place to start:

'Display Calibration: Root Fundamentals'
http://www.avsforum.com/avs-vb/showthread.php?t=1021933

The vast majority of video consumers have less than a half-vast foundational understanding of even the simplest video basics. Most videophile hobbyist types learn bits and pieces of randomly accumulated information over time, rather than from structured, methodical, disciplined, formal instruction. Many forum members have learned largely from other members. These forums are a mixed bag of good and bad information, from mostly well-meaning but partially informed enthusiasts. Many make assumptions based upon insufficient or faulty information. Confident assertions abound, but often only mislead and misinform readers who have no foundation in imaging science fundamentals, or video industry standards and recommended practices. Much of what is said in the display owner segments of the forum is based primarily on anecdotal observations, opinions, and experiences of consumers. Consumer video product marketing hyperbole is also a culprit.

Video is science in the service of art. There can be no coherent video industry without a disciplined adherence to industry standards and recommended practices. The American video system in the days before digital TV was called NTSC ( referring to the National Television System Committee). For many decades there was not the kind of discipline in the system we see today. There was such chaos that it was cynically referred to as "Never The Same Color." A pivot point was reached when Joe Kane chaired a SMPTE working group studying broadcast monitors in the mid '80s, then was encouraged by the group to promote their findings and recommendations to other professionals, display manufacturers, and consumers. Joe Kane also co-founded the Imaging Science Foundation with the current President, Joel Silver. About that time Joe also produced the first display calibration program on optical disc used by consumers and professionals alike. It was on laserdisc and titled: 'A Video Standard.' The AV Science Forum founders were significantly inspired by these efforts.

Imaging science and display standards became popular topics in the video hobbyist print media of the day. Better informed consumers, with laserdiscs in hand, began confronting TV retailers about the poor performance of their wares, and their TVs not being capable of displaying correct video pictures. TV manufacturers started to improve their products. The ISF began getting traction in their efforts to get display manufacturers to include more features and options for calibrating their equipment properly.

The most readily accessible resource for studying imaging science and display standards, along with how to correctly evaluate and adjust video systems, is the popular tutorial programs available on optical disc. They are a great way to begin a more reliable study of how video and displays actually work. Another good historical resource is available in PDF format from 'Widescreen Review.' Here's a link where you can purchase it: http://shop.widescreenreview.com/products/Imaging-Science-Theatre-2000-%28Digital-Download%29.html .

Only a solid foundation in imaging science fundamentals, plus display industry standards and practices, can prevent false assumptions and misconceptions about how video works, and what displays do. It just takes time and effort to establish an understanding of these fundamentals. Excellence in any endeavor requires extra devotion and persistence. The reward is better pictures. As Joe Kane insists: "It's all about the art."

Yet the Display manufacturers apparently still consider calibration 'out of the box' to be unnecessary.
They may supply a CMS but for some reason do not use it themselves. Why should this be?
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post #54 of 97 Old 07-29-2013, 09:37 AM
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Originally Posted by GeorgeAB View Post

.....TV manufacturers started to improve their products. The ISF began getting traction in their efforts to get display manufacturers to include more features and options for calibrating their equipment properly.....

Yet the Display manufacturers apparently still consider calibration 'out of the box' to be unnecessary.
They may supply a CMS but for some reason do not use it themselves. Why should this be?
Your question has been asked and answered hundreds of times over the years in this and many other forums. Here is a link to a fairly comprehensive and very clear answer: http://www.tlvexp.ca/2011/12/why-tvs-are-not-calibrated-from-factory/ . You will also find that site to be a gold mine of practical, simple, and helpful information about video.
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Your question has been asked and answered hundreds of times over the years in this and many other forums. Here is a link to a fairly comprehensive and very clear answer: http://www.tlvexp.ca/2011/12/why-tvs-are-not-calibrated-from-factory/ . You will also find that site to be a gold mine of practical, simple, and helpful information about video.

Thanks George.

Sorry if it is 'old hat' to you.

It must be rather frustrating for you to have to reply in such a manner to ignorant people (like me).

Incidentally, how much content on any of the forums is new?
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post #56 of 97 Old 07-29-2013, 10:28 AM
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Originally Posted by GeorgeAB View Post

Your question has been asked and answered hundreds of times over the years in this and many other forums. Here is a link to a fairly comprehensive and very clear answer: http://www.tlvexp.ca/2011/12/why-tvs-are-not-calibrated-from-factory/ . You will also find that site to be a gold mine of practical, simple, and helpful information about video.

Thanks George.

Sorry if it is 'old hat' to you.

It must be rather frustrating for you to have to reply in such a manner to ignorant people (like me).

Incidentally, how much content on any of the forums is new?
There's no need to apologize for not knowing something. We are all ignorant on different subjects. As a wise man from history said: "There is nothing new under the sun." However, a given topic may be new to you.

You may notice a lot of forums have what some call "sticky" threads posted repeatedly at the top of a given topical section of discussion. These tend to address frequently asked questions to save time and space and limit redundancy. They are also called "FAQs." These are often a good place to start when new to a subject or forum.

Most consumers know very little about how video works. A large portion of those don't want to know all the gory details, nor want to be burdened with extra complexity. Most consumers want cheap, simple, easy and convenient......and maybe shiny .....and thin. The passion for excellence is a relatively rare commodity. Consumer electronics manufacturers understand the mass market better than a lot of the buying public do. Readers of this and similar hobbyist forums are a tiny fraction of the mass market.
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post #57 of 97 Old 07-29-2013, 10:44 AM
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@GeorgeAB

Not to in any way justify my previous post but I read somewhere on another forum that even very expensive reference monitors (used no doubt by Professionals) come without any calibration.

My thoughts were that perhaps there are scientific rather than the usual financial / marketing reasons not to do so.
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post #58 of 97 Old 07-29-2013, 11:11 AM
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@GeorgeAB

Not to in any way justify my previous post but I read somewhere on another forum that even very expensive reference monitors (used no doubt by Professionals) come without any calibration.

My thoughts were that perhaps there are scientific rather than the usual financial / marketing reasons not to do so.
I read somewhere?
On another forum?
My thoughts?
Perhaps?
You're being too vague. Please provide specifics. Don't you think pro monitor manufacturers would have financial/marketing reasons for how they conduct their business? Have you considered that there might be practical technical reasons why a display would not be completely calibrated until it is sold and installed in a specific system?
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post #59 of 97 Old 07-29-2013, 01:35 PM
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I read somewhere?
On another forum?
My thoughts?
Perhaps?
You're being too vague. Please provide specifics. Don't you think pro monitor manufacturers would have financial/marketing reasons for how they conduct their business? Have you considered that there might be practical technical reasons why a display would not be completely calibrated until it is sold and installed in a specific system?

As an ignorant amateur calibrator I cannot think of a reason why it should not be calibrated, unless of course (as the original poster asks) it is not always to D65.

You are right that I have considered the reasons that is why I ask the question not knowing the answer.
Cannot imagine it is financial or marketing but what do I know?

My vagueness was deliberate not wishing to incur the anger of the AVS moderator Police. I will find the post (which hopefully you may approve of) and post a reference on this thread.

Please forgive my uncertainties, video science (or any other science for that matter) is littered with opinions that are misrepresented as facts.
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post #60 of 97 Old 07-29-2013, 02:30 PM
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As an ignorant amateur calibrator I cannot think of a reason why it should not be calibrated, unless of course (as the original poster asks) it is not always to D65.

Dcinema has a non-D65 white point and photography and graphics art industries often use D50.

The standard in the US is rec.709 for all HD content. All of the current best practices would recommend using D65.

The vast majority of professional displays come with a D65 setting that is at least somewhat calibrated.

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