Originally Posted by HoustonHoyaFan
I have to disagree with you.
Right now on/off CR is useless given that we now have dynamic dimming systems that can totally shut off on a black screen or get so close the the resulting measurement is meaningless.
Well sorry, but I have to strongly disgree with you
Published ∞:1 figures for ON/OFF contrast ratios, with dynamic dimming systems that can totally shut off on a black screen, are "useless" in that they are completely meaningless with respect to telling you anything with respect to what is the ON/OFF contrast performance with actual content. For this reason I roll my eyes every single time I see them.
In such circumstances, such as with respect to the SONY 885/760ES by the way (since I saw you asked the question over in the owner's thread, let me answer that for you here at the same time
) absolutely the WRONG way to measure ON/OFF contrast with full dynamic dimming that will trigger shutting off of the light engine in response to a frame of full field black 16, is to measure full field white 235 vs full field black 16. The CORRECT method is to input a full field black 16 with singular white pixel in one of the corners of the image, such that the shutting off of the light engine is not triggered and thereby you can accurately measure what is the ON/OFF contrast without the influence of the dynamic dimming triggering shutting off of the light engine.
This yields the true ON/OFF performance measurement, being the ON/OFF contrast performance with actual content, which is absolutely NOT "useless" !
For example, in the instance of the SONY 885/760ES this reveals that there is not a significant difference with respect to ON/OFF contrast performance with the dimming set to full as compared with limited and overall only a circa 40% increase as compared with OFF. And that the maximum ON/OFF contrast performance of that projector is circa 23,000:1. How is this "useless"? In short, it's not. It's extremely vital information.
Hence, the only time an ON/OFF contrast ratio measurement is "useless" is when it's not carried out properly or in the correct manner.
Originally Posted by HoustonHoyaFan
The ANSI pattern was designed to give a more meaningful figure-of-merit of an intra-scene contrast but it is very tedious because you have to take 16 measurements. 12 years ago Greg Rogers popularized the M-ANSI which just measured the center 4 squares, so just 4 measurements. It became somewhat of a standard for projector measurements on AVS.
Today the intra-scene contrast measurement that is popular in the flat panel industry (used by RTings.com and HDTVTest) and also in the broadcast/pro space is a 2 measurement system that just measures the center white and center black squares or a full field white and a center black square.
The benefits are obvious:
1) You are measuring a single frame pattern so the "turn off on a full black screen" DD systems gets defeated.
2) You are measuring the center black (surrounded by 4 white squares) so you capture the black level with the worse case light pollution.
Give it a try!
Sorry, but that's just being lazy. These days (as opposed to 12 years ago) with the right equipment and experience taking those 16 measurements hardly takes any time at all.
There is solid rationality and science behind the ANSI contrast parameter and corresponding checkerboard pattern. Taking a single measurement of only one square for white and black is not even remotely as useful information as the proper ANSI contrast measurement. So don't be lazy! Taking a single measurement in the middle of the screen is just plain wrong and not very helpful for so many reasons. I could give you a very lengthy list. At the top of that list is the fact that most projectors do not have perfect luminance uniformity across the whole image and the variance can be considerable, causing the 8 white (and black) measurements to also have considerable variance. Wherein, a singular measurement in the middle is completely meaningless and hence useless. And that's just the tip of the iceberg.
So if you don't mind I'll carry on taking my measurements properly and accurately and continue to report accurate and useful ON/OFF contrast and ANSI Contrast performance.
And as and when I have opportunity to take those measurements with respect to SAMSUNG's The Wall and IF series I will be sure to publish those measurements on here. Actual accurate ON/OFF and ANSI Contrast measurements are a damn sight more useful than a singular measurement of one ANSI square, absolutely no question about that.
So sorry to hear you disagree. But with with respect I cannot agree with you and for very good reasons.