Does anyone actually believe the nonsensical contrast ratios specs? - AVS Forum
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post #1 of 185 Old 02-17-2014, 08:46 PM - Thread Starter
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Every time I see a review or an article the 1st thing that is brought up is the improvement in contrast ratio from last years model. " model xyx now has a contrast ration of a 1,000,000:1 vs last years of on 500,000:1"
What a bunch of BS!

It reminds me of the early days of amplifiers. Manufactures would just come up with some ridiculous figure.
We used to call these ILS ratings-if lighting strikes. biggrin.gif

End of rant.....
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post #2 of 185 Old 02-17-2014, 08:58 PM
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There are some companies you can actually trust. Off the top of my head JVC, Runco, Sim2, and Sony typically fall very close to the claimed specs. The JVCs truly do have up to 150000:1 contrast and with the new DI even higher dynamic contrast. You'll find that many, but not all, projector companies are fairly honest
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post #3 of 185 Old 02-17-2014, 09:24 PM
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Yep, Seegs beat me to it. JVC, at least, are usually measured by Cine4home (a highly technical German AV website) as coming in very close to their advertised specs for native contrast.
(That also went for the very technical reviews by Greg Rogers of Widescreen review, where the JVC projectors tended to measure near or at their rated contrast specs).

Cynicism can be healthy, but don't let it also lead you to think *everything* is b.s. - then you'll miss out on the items that are the real deal.
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post #4 of 185 Old 02-17-2014, 11:04 PM
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Often the pj's can reach the spec but in some horrible dynamic mode with garish colors and horrible di pumping or maybe first after several minutes of a black scene. In other words, in theory the specs are true but in a completely useless mode. This is also somewhat a problem with jvc. Yes they can reach 150k native, but only at max tele throw and the iris closed down to a pinhole leaving 150-200 lumens. Not very useful to most people. The lower models with only one iris drops less dramatically in light output though iirc. The light outout and native contrast specs are also found in diametrically opposed and mutually exclusive iris/throw modes... Here the di really helps giving you both worlds with regards to the iris (with some added artifacts) albeit not the the throw ratio. The light output spec is also not in a calibrated mode. The safest bet is to look for independent measurements.
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post #5 of 185 Old 02-18-2014, 07:36 AM - Thread Starter
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So can we agree that the full on/off method is a complete farce?
It's like saying I have 300 mph tires wink.gif
Given that our eyes only have the ability to see 100:1 in most situations to 10000:1 under absolutely ideal conditions and that as contrast increases our ability to discern differences diminishes very quickly what's the point?
I have measured real world contrast ratios of projectors that have rated on/off in the 100,000s and routinely see low 100s.
ANSI contrast should be the only benchmark that actually has anything to do with the real world.
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post #6 of 185 Old 02-18-2014, 07:59 AM
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You're right, there is no benefit to higher contrast ratios, it is all a farse. We never saw any improvement in black levels with those silly Kuro plasmas. The new JVCs look exactly the same with full black outs as last years and all those "numbers" are just a marketing gimmick. Thanks for saving us all that grief. Now I can safely just buy a first generation DLP and be a happy camper since I won't see any real improvement in contrast anyways with my faulty eyeballs.

Really, how many times do we have to hear people start in on this topic that have absolutely no idea what they are talking about. Can't wait to hear Darin chime in here when he wakes up.

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post #7 of 185 Old 02-18-2014, 08:05 AM
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Why doesn't everybody just use ANSI? Seems like it would make it easier to compare PJ's under real world conditions. Seems like lumens should be reported after calibration, too.
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post #8 of 185 Old 02-18-2014, 08:17 AM
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Because ANSI is such a small part of the overall contrast performance of the display. You'd be surprised how much on/off controls the black of a display compared to ANSI. Plus it doesn't take long before you hit a level where gains in ANSI do nothing more for the image. It is also incredibly hard to measure accurately.

Also, lets talk about how ANSI would relate to the "black levels" of a display. What display would you say has better black levels, a Sony G90 or a Panasonic AE7000?? Now tell me which one has a better ANSI contrast value. How about a JVC X500 compared to a Marantz 11S1? When we did comparisons of a RS35 to a Samsung DLP the Samsung trounced the JVC for ANSI measurements but we couldn't find A SINGLE CLIP that looked better on the Samsung for contrast, not one.

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post #9 of 185 Old 02-18-2014, 08:52 AM
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Quote:
Originally Posted by trans_lux View Post

So can we agree that the full on/off method is a complete farce?
It's like saying I have 300 mph tires wink.gif
Given that our eyes only have the ability to see 100:1 in most situations to 10000:1 under absolutely ideal conditions and that as contrast increases our ability to discern differences diminishes very quickly what's the point?
I have measured real world contrast ratios of projectors that have rated on/off in the 100,000s and routinely see low 100s.
ANSI contrast should be the only benchmark that actually has anything to do with the real world.

Cue DarinP in 5...4...3...2....
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post #10 of 185 Old 02-18-2014, 08:59 AM - Thread Starter
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Your missing my point entirely. I'm trying to discuss the fact that everyone looks at a spec that is completely meaningless. Hell it does not even have a standard for how the measurements are derived. These numbers are made up-end of story.

And for your information i do know what I'm talking about. I have been involved in projection video longer than most of you have been alive. I go all the way back to Kloss Nova Beams. smile.gif

I also have proven hard science and facts on my side.
Let me find some articles from people you may trust.
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post #11 of 185 Old 02-18-2014, 09:08 AM
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Oh, not this again....

Here are some facts (measurements) about projector contrast performance:
http://www.avsforum.com/t/852467/avs-contrast-thread-now-with-dynamic-contrast-results

ANSI is a very poor approximation of real world picture content, it has an average display luminance of 50%, real world content is much, much lower than that, like 5-10% (often even lower):
http://www.avsforum.com/t/1046712/avs-apl-study-adjunct-to-avs-contrast-project

And this whole "100:1" static contrast ratio completely ignores the fact that that's with your eye stationary, reality is that your eye can move around the screen and adjust to the luminance in different areas of the screen.

See what an anamorphoscopic lens can do, see movies the way they were meant to be seen
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post #12 of 185 Old 02-18-2014, 09:15 AM - Thread Starter
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Actually your eyes ability to perceive contrast ratio resets ever time it moves.

Here is one article-I know Cnet can be taken with a grain of salt I will find others...

http://m.cnet.com/news/one-million-to-one-why-contrast-ratio-is-the-dr-evil-of-hdtv-specs/10148015
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post #13 of 185 Old 02-18-2014, 09:23 AM
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Quote:
Originally Posted by trans_lux View Post

Your missing my point entirely. I'm trying to discuss the fact that everyone looks at a spec that is completely meaningless. Hell it does not even have a standard for how the measurements are derived. These numbers are made up-end of story.

Can you explain, then, why the most technically careful reviews of the JVC projectors (e.g. Greg Rogers of Widescreen Review and the Cine4home site) have found that the contrast they measure from the JVC projectors tracks so closely to those advertised by JVC, year after year?

Coincidence?

While you are at it, could you explain why people routinely see differences in contrast between displays with contrast ratios far outside that which you claim our eyes will perceive?
For instance, are the kudos for Kuro plasmas or the new OLED technology just some sort of coincidental, mass delusion that anyone can actually see the difference compared
to an average LCD screen? No one really sees the difference between a JVC projector's contrast and some old DLP or LCD projector?
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post #14 of 185 Old 02-18-2014, 09:27 AM
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Just read the CNET article. Great article for telling you absolutely nothing except that they don't know how to measure contrast, don't understand it and want to make sure you know most manufacturers don't either. Nothing at all about the benefits of contrast to an image, or how that ANSI checkerboard pattern reflects about 1% of real image viewing making it worthless as a measure of contrast. But keep going, I can't wait to see your next "hard science and facts" article.

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post #15 of 185 Old 02-18-2014, 09:30 AM
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Here is an article about contrast ratio by someone who actually knows what he's talking about:

http://www.hometheaterhifi.com/volume_13_2/feature-article-contrast-ratio-5-2006-part-1.html

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post #16 of 185 Old 02-18-2014, 10:10 AM
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Quote:
Originally Posted by trans_lux View Post

Given that our eyes only have the ability to see 100:1 in most situations to 10000:1 under absolutely ideal conditions ...
Where did you get that 100:1 number? You say you have scientific data to back up your claim, so I would love to see where you got that. I wonder if it came from somebody who had a reading comprehension problem and thought that scientific data which shows that humans have trouble seeing differences of less than about 1% (which gets a score of about 100 after a reciprocal is applied) somehow meant that humans couldn't see more than 100:1. People taking something about not being able to see much less contrast ratio than 1.01:1 and thinking it meant they can't see more than 100:1 contrast ratio would be funny if it weren't sad.
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Originally Posted by trans_lux View Post

ANSI contrast should be the only benchmark that actually has anything to do with the real world.
You told us you go way back, so here are some basic questions you should be able to answer:

1. How well did CRTs do for showing blacks as black compared to early digitals, in general?
2. How did ANSI CRs of CRTs compare to those of early digitals in general?

If you know as much as you seem to think you know you should be able to answer those.

This is a strange industry IMO. Kind of like if the car industry had professionals who claimed that what the Honda Civic is good at is how you decide how fast a car will go around a racetrack, while claiming that what the Ferrari is good at is irrelevant.

Consumers can look at displays where the only significant difference is something that many professionals say they wouldn't be able to see, yet they see it and appreciate it.

Specs aren't what matters. Actually performance is. And actual on/off CR (native and dynamic) is very important for many reasons. I could go on, but you really should be able to answer my 2 basic questions above and then we could go from there.

--Darin

This is the AV Science Forum. Please don't be gullible and please do remember the saying, "Fool me once, shame on you. Fool me twice, shame on me."
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post #17 of 185 Old 02-18-2014, 10:18 AM
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For those interested, here is some information from a company (Dolby) that has a display where they can tune both ANSI CR and on/off CR and find what people can see and not see, as well as what people seem to prefer or not. I am a reviewer for an industry standard with one of their top people and have discussed it with them, as well as getting a demo and discussing it many times with the company that originally developed the technology (before Dolby bought them). It is very clear with their display that on/off CR matters and people can see big differences with different on/off CRs.
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Originally Posted by vtms View Post

As people should be able to see, their figure for "Eye Instantaneous" is about 100,000:1 although I think they may be taking a shortcut and allow some adjustment when looking around a single image for their "Instantaneous" figure. It doesn't take into account how the eye can adjust from very bright images to very dark images separated in time within the same movie though.

--Darin

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post #18 of 185 Old 02-18-2014, 10:26 AM
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Totally true. While ANSI can have some effect on perceived intra-scene contrast, as Kris pointed out, once you reach a high enough number it's effectiveness wears off whereas on/off goes considerably farther on our eyes.

I think the latest Panasonic plasmas measure over 15000:1 ANSI or some crazy high number like that but as far as image "depth" goes regarding contrast, in the correct environment, my JVC can look basically just as good even though it can only muster around 300:1 ANSI.
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post #19 of 185 Old 02-18-2014, 12:07 PM - Thread Starter
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As for your questions agree with your point.

I'm not suggesting that there has not been improvements made in contrast ratio that can be perceived-there certainly has.
Again my point is why use a metric that has absolutely no standard and is open to gross manipulation?
Further its using values that are so far beyond human vision that it makes no difference.
I think these are important topics to discuss as many are unaware and use this as a deciding factor when making a decision.

Question for you? Why would companies and industries that supply mission critical solutions such as Barco, DPI, Christie etc. only use Ansi contrast?
Because it is the only measurement for contrast that has actual standards and real world value.
Quote:
Image contrast is definitely not to be related to projector or LCD panel brochure contrast ratios. They use the so-called ‘on/off’ method. It’s a sequential test: Measure a full white field, then measure a full black field. This has limited use for product comparison, and is no use for image quality assessment. You will see figures of quoted in excess of 1000:1.


http://www.avinteractive.com/news/products/whitepapers/42989/ansi-standard-achieves-visibly-and-measurably-better-screen-images

Also what device is capable of measuring such high on/off ratios?


Here is some science that may be helpful

http://wolfcrow.com/blog/notes-by-dr-optoglass-dynamic-range-of-the-human-eye/

http://www.poynton.com/notes/Timo/Weber_and_contrast_ratio.html
Quote:
Although the human eye is capable of a contrast ratio of 1 or 2 million to 1, (about 20 stops), from midnight black to bright sunlit white, yet it takes the eye some time to adjust to these extremes. For the purposes of photography we are interested in its instantaneous dynamic range, about which there is some disagreement, but it is of the order of 1000:1footnote 2 (about 10 stops).

http://warrenmars.com/photography/technical/resolution/human_perception.htm
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post #20 of 185 Old 02-18-2014, 12:57 PM
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Quote:
Originally Posted by trans_lux View Post

As for your questions agree with your point.

I'm not suggesting that there has not been improvements made in contrast ratio that can be perceived-there certainly has.
Again my point is why use a metric that has absolutely no standard and is open to gross manipulation?
Further its using values that are so far beyond human vision that it makes no difference.
I think these are important topics to discuss as many are unaware and use this as a deciding factor when making a decision.

Question for you? Why would companies and industries that supply mission critical solutions such as Barco, DPI, Christie etc. only use Ansi contrast?
Because it is the only measurement for contrast that has actual standards and real world value.
http://www.avinteractive.com/news/products/whitepapers/42989/ansi-standard-achieves-visibly-and-measurably-better-screen-images

Also what device is capable of measuring such high on/off ratios?


Here is some science that may be helpful

http://wolfcrow.com/blog/notes-by-dr-optoglass-dynamic-range-of-the-human-eye/

http://www.poynton.com/notes/Timo/Weber_and_contrast_ratio.html
http://warrenmars.com/photography/technical/resolution/human_perception.htm

What gross manipulation? Again, you're assuming that ALL contrast measurements are bogus, this is simply not the case. There are plenty of manufacturers and publications that provide valid contrast ratio measurements. Just like there are plenty of publications that point out the falsehoods of contrast measurement claims that are bogus.

Other than the work done by Brightside and later bought by Dolby, I haven't seen a display that couldn't benefit from improvements in ON/OFF contrast. ANSI contrast measurements on plasmas have exceeded what you're referring to for years now, yet we still see improvements being made in black and contrast. If that isn't from ANSI, what is it??

If a digital projector with 1000:1 ANSI contrast has worse blacks and image contrast than a Sony G90 with about 100:1 ANSI contrast, why does the Sony look better for blacks and overall image contrast??

Tell me what the real world value of ANSI contrast is? Tell me how to measure it (so that it is valid and not compromised) in a room? I would love to hear your explanations for either of these questions.

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post #21 of 185 Old 02-18-2014, 01:21 PM
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Quote:
Originally Posted by trans_lux View Post

As for your questions agree with your point.
What is it you are agreeing with?

Not sure why you skipped these:
Quote:
Originally Posted by darinp2 View Post

1. How well did CRTs do for showing blacks as black compared to early digitals, in general?
2. How did ANSI CRs of CRTs compare to those of early digitals in general?
If you won't answer them or say that you aren't sure of the answers I don't think there is a lot of point to addressing any of your questions.

You are very misinformed about this subject matter. If you care you should address those questions IMO. If you don't care then there isn't a whole lot anybody can do other than make it clear to others that you are wrong.

--Darin

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post #22 of 185 Old 02-18-2014, 01:31 PM - Thread Starter
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So you agree that many manufactures claims of on/off contrast ratios are misleading at best?
Further how is using a full white image ON then a completely black image OFF in a black box pointing into the lens at an unknown distance with absolutely no ambient light present representative of real world use?
And this is a big if its that's actually the procedure as there is no standard and no equipment capable of taking these measurements.

Ansi isn't perfect but its significantly better than a measurement that has ZERO standards.

Your CRT vs early digital proves the point. As I recall no 1st gen digital projectors had 1000:1 ANSI contrast ratios or high on/off specs as most were truthful.
Early digital projectors claim as on/off contrast ratios were 200:1, 300:1 so how in a roughly short period of time-10 years or so- was such an exponential increase in contrast performance achieved?
Even JVC was honest then http://www.projectorcentral.com/JVC-DLA-M15U.htm

Also you didn't answer my question re: why ansi contrast is used as the only standard for professional displays and industries.

I just find it so disingenuous and morally reprehensible that manufactures and really an industry hang their collective hats on such junk science ultimately misleading consumers.
Its just so wrong....
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post #23 of 185 Old 02-18-2014, 02:00 PM
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Quote:
Originally Posted by trans_lux View Post

So you agree that many manufactures claims of on/off contrast ratios are misleading at best?
Further how is using a full white image ON then a completely black image OFF in a black box pointing into the lens at an unknown distance with absolutely no ambient light present representative of real world use?
And this is a big if its that's actually the procedure as there is no standard and no equipment capable of taking these measurements.

Ansi isn't perfect but its significantly better than a measurement that has ZERO standards.

Your CRT vs early digital proves the point. As I recall no 1st gen digital projectors had 1000:1 ANSI contrast ratios or high on/off specs as most were truthful.
Early digital projectors claim as on/off contrast ratios were 200:1, 300:1 so how in a roughly short period of time-10 years or so- was such an exponential increase in contrast performance achieved?
Even JVC was honest then http://www.projectorcentral.com/JVC-DLA-M15U.htm

Also you didn't answer my question re: why ansi contrast is used as the only standard for professional displays and industries.

I just find it so disingenuous and morally reprehensible that manufactures and really an industry hang their collective hats on such junk science ultimately misleading consumers.
Its just so wrong....

I do agree that there are manufacturers whose claims for contrast ratio are misleading. I also agree that most manufacturers use a lot of misleading advertising to drum up business. That doesn't mean that high contrast ratios don't exist or are worthless, only that some companies aren't honest in how they report them.

What is the point of a black level measurement if you don't know what the white point is capable of? You need to know the full range, hence ratio. As mentioned before what is the point of a contrast ratio of 150,000:1 if the best white point you can achieve with it is 3 fL. One needs to know the performance capabilities of the display being tested so that they can make an informed choice on the display for their own viewing enviroment.

Measuring on/off contrast is not difficult and there is plenty of test equipment that can be used to do it properly and give accurate readings. The fact that you don't think there is shows how little you really know about video measurements.

The reason a lot of early digital projectors didn't have high on/off contrast ratios is because they weren't capable of high on/off contrast ratios. There is no conspiracy here. Got back ten years ago and look at the black levels of most digital projectors, they sucked. The JVC you linked to isn't even a home theater projector but a business projector. It doesn't even use the panels JVC later designed that created a breakthru in contrast performance. Again, showing more and more how little you know about video and measurements.

ANSI is reported by most DLP based manufacturers because it is the only contrast measurement they've made advances in. Their on/off contrast performance (especially in the commercial space) is horrible and their total lumen output is far more important for that venue than their total on/off contrast. Even ANSI doesn't matter that much considering the venue's ambient lighting (exit signs, led rope lighting, reflections). Home theater is a completely different animal considering that your viewing enviroment can be controlled completely and you don't need insane lumen output to get a bright image. And please, make absolutely no mistake about this, if Barco or any other commercial DLP projector manufacturer, could make massive advances in overall on/off contrast performance they'd be beating that drum ALL DAY LONG. It would give them a huge leg up for display capability. Ever go to a digital cinema and watch a movie? Ever notice how the black levels in theaters absolutely suck?? I bet the ANSI contrast of a Barco DCI projector is considerably higher than most consumer projectors on the market today. Think their black levels are anywhere near as close???

I find it disingenuous and reprehensible that someone can come into a science forum and spout out untruths and attack those that actually know what they are talking about and then try and claim their complete ignorance as scientific fact. Even a minimal amount of knowledge in video systems and measurement would completely disprove most of what you're saying.

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post #24 of 185 Old 02-18-2014, 02:11 PM
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trans_lux,

If you won't actually answer both my questions will you at least answer the first one:

1. How well did CRTs do for showing blacks as black compared to early digitals, in general?

I don't feel like wasting my time with such misinformation as yours if you won't even answer such as simple question.

I will address one thing about one of your questions. Do I really need to explain why companies that have products that excel in one kind of measurement try to push that as the one that matters? There are gullible people, for one and marketing departments market. ANSI CR was also a good test when CRTs were basically the only thing out there. That changed with digitals came along as would be evident if you actually knew the answers to both those questions I asked.

I'll ask another. Why did the experts at the time think that the sun and planets all went around the earth? In short, they were ignorant. Here are 3 things I would say all seem logical to some people, but are all false today:

1. The sun goes around the earth.
2. The earth is flat.
3. ANSI CR matters and on/off CR does not.

I can explain why measuring full white and full black matters to real world viewing when people turn off their other lighting, but here is an excercise for people who aren't sure. On the latest Spears and Munsil test disc there is a pattern that is a 4x4 checkerboard, but the brighter rectangles are about 5% video level (instead of 100% video like on the ANSI CR pattern). It is a very dark pattern, but mixed. Here are some things that people can think about relative to that pattern:

1. About how bright should the 5% rectangles be relative to 100% video level (white)? Don't forget gamma.
2. What does ANSI CR tell us about the kinds of intra-image CRs we are likely to get for that pattern?
3. If you only had 1000:1 on/off CR to work with, what kind of intra-image contrast ratio do you think you would achieve with that pattern? Would improving on/off CR beyond 1000:1 be likely to help the intra-image contrast ratio you could achieve with that pattern?

--Darin

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post #25 of 185 Old 02-18-2014, 02:18 PM - Thread Starter
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All I was looking for was a spirited debate on a topic that I find interesting and important.

Despite pointing to several facts on the subject you dismiss my opinion and personal experiences as nonsense as clearly you are the definitive expert.

There's always someone hiding behind the keyboard that has to make it personal.

I'll continue to enjoy my lowly 5000:1 Titan Reference I hope you do the same with your JVC.
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post #26 of 185 Old 02-18-2014, 02:21 PM
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Quote:
Originally Posted by trans_lux View Post

Again my point is why use a metric that has absolutely no standard and is open to gross manipulation?

IF (and this seems like a big if given your posts) that is your point, I agree, it would be nice if there was a standardardized method for measuring sequential contrast. Something with requirements like only measuring without changing settings on the machine, and black/white measurements being made some reasonable time period. I think this would be a nice improvement. It still wouldn't solve the problem of manufacturers measuring in "unusable" modes (caugh Panasonic), but it would stop the bogus measurements where the lamp or manual iris is changed in between.
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Further its using values that are so far beyond human vision that it makes no difference.

What are you basing this on? We have hundreds of eye witness reports that (just picking a recent example) the new JVCs with dynamic iris (350,000:1 sequential contrast) are a substantial improvement over the prior years (50,000:1 sequential contrast).

Here's another thread that discusses this:
http://www.avsforum.com/t/1071092/poll-how-much-on-off-contrast-is-enough

Here is the salient info:
http://msis.jsc.nasa.gov/sections/section04.htm#_4.2_VISION

The range of human vision is (see link for reference) on the order of 10^15, or 1 quadrillion. Now OK, that includes damaging levels, but if we assume a "usable" range of below the threshold of vision to white paper in sunlight that's 10^10, or about 10 billion. We aren't anywhere close to that.

If we want to "produce" actual black, given a reference light output of 12ftL, we still require a black level that is over 10 million times dimmer to be unable to see it.
Quote:
I think these are important topics to discuss as many are unaware and use this as a deciding factor when making a decision.

Perhaps, but your broach the subject in such a way as to make meaningful discussion almost impossible, ie claims that are easily disprovable like, the above, or your 100:1 maximum comment.
Quote:
Question for you? Why would companies and industries that supply mission critical solutions such as Barco, DPI, Christie etc. only use Ansi contrast?
Because it is the only measurement for contrast that has actual standards and real world value.

It may be the because it is the only one with a standard. That said let me throw this back at you:

Version 1.2 of the DCI Digital Cinema System Spec states the following:
Quote:
8.3.4.7.
Sequential Contrast
The sequential contrast ratio is computed by dividing the white luminance (of a peak white field) by the black luminance (of a black field). The nominal (reference) value is required to have a minimum sequential contrast of 2000:1. The tolerances for mastering and exhibition are shown in Table 11: Reference Image Parameters and Tolerances. In order to eliminate unwanted detail or discoloration in near blacks, it is critical that Mastering Projectors have an equal or higher sequential contrast than all exhibition projectors.
Note that this is a measurement of the sequential contrast of the system. It includes the projector and the ambient light on the screen.

If ANSI contrast is the only thing that has "real world value" why did DCI write into the specification for digital cinema a requirement for a minimum sequential contrast?

The answer is because it matters. It should also be noted that there is no requirement in the DCI Digital Cinema System Spec for an ANSI contrast value.

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Originally Posted by trans_lux View Post

Further how is using a full white image ON then a completely black image OFF in a black box pointing into the lens at an unknown distance with absolutely no ambient light present representative of real world use?

Because it measures the two extremes which the device must be able to reproduce. It must be able to reproduce peak white (measured by the white image) and complete black (measured by the black image). Real world content makes use of both. If black level is high, space looks milky/gray instead of black, if white is low, snow capped peaks look dim and dingy. Since contrast is white/black, a high contrast ratio is important. It should also be noted again, that very, very few scenes have 50% average luminance, which is what ANSI measures. Most scenes where black really matters are closer to (or lower than) 1%.
Quote:
Also you didn't answer my question re: why ansi contrast is used as the only standard for professional displays and industries.

It's not, DCI requires Sequential Contrast measurements, but NOT ANSI.

See what an anamorphoscopic lens can do, see movies the way they were meant to be seen
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post #27 of 185 Old 02-18-2014, 02:24 PM
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Quote:
Originally Posted by trans_lux View Post

All I was looking for was a spirited debate on a topic that I find interesting and important.
If that is what you wanted why does it seem so important to you not to answer:

1. How well did CRTs do for showing blacks as black compared to early digitals, in general?

We could move on and discuss things, but you seem dead set and making sure we can't address that other the other question since you won't give straight answers to them. You can blame others if you want, but if you really wanted to move toward the truth you would just answer them instead of complaining that somebody wouldn't answer all your followup questions when you wouldn't even answer a simple question they had already asked.

I think you will prove you don't really care what the truth is if you won't even address those 2 questions I asked.

I may address them for other people eventually.

--Darin

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post #28 of 185 Old 02-18-2014, 02:37 PM
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Quote:
Originally Posted by trans_lux View Post

All I was looking for was a spirited debate on a topic that I find interesting and important.

Despite pointing to several facts on the subject you dismiss my opinion and personal experiences as nonsense as clearly you are the definitive expert.

There's always someone hiding behind the keyboard that has to make it personal.

I'll continue to enjoy my lowly 5000:1 Titan Reference I hope you do the same with your JVC.

A debate requires a question. What you seem to be looking for here is a bunch of people giving you high fives and agreeing with you. The very first post is a statement, not a question for debate. And its is a TOTALLY off base statement that flies in the face of any logic if you know about video. And I'm certainly NOT hiding behind a keyboard; notice MY NAME clearly right next to my post and my credentials (in this industry anyways) clearly at the bottom of my post?? So was it your Mom or Dad that named you trans_lux??

Bring your Titan Reference over to my house and lets measure its ANSI contrast compared to my JVC (don't worry, I have meters that can actually measure contrast, no funny sci-fi magic here). Then lets talk about which one has better blacks and contrast with absolutely any content you wish to show. Should be fun and enlightening.

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post #29 of 185 Old 02-18-2014, 02:38 PM
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I'm going to go against the grain a bit here I guess, but I actually think ANSI contrast values far less important than on/off values.

pretty much every display on the market today has good enough ansi contrast that when watching a bright image, 'black' looks absolutely black to me. on the other hand, maybe 1% can produce a black level that actually looks blacks during dark scenes or fade to black.

for my enjoyment, I'm more interested in how close to black a display can get during a dark scene, and don't really care at all about whether it can hold that black level during a super bright scene.

if I'm going to play conspiracy theorist, I think the hype around ANSI contrast values was created to make plasma and lcd technologies actually look like an improvement over crt. which is funny, because except for the absolutely best flat panels, I've always thought crts had much better 'contrast' performance.

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post #30 of 185 Old 02-18-2014, 02:42 PM
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On/Off contrast is typically a value that people/manufacturers try to claim isn't important because they don't do well at it. Yet more than any other measurement it directly impacts the overall contrast performance and black floor of the display. Now here we are talking about high dynamic range for the next generation video displays and formats. What's the point? If we are limited to 100:1 we shouldn't see any improvement anyways? ANSI contrast is already through the roof with plasma displays, there is no room for contrast performance enhancements. What are all these crazy engineers going on about now!!!

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