Originally Posted by HogPilot
cite some of your sources pertaining to both human iris response speeds as well as static contrast ratio? Please don't take this as me challenging you - I have absolutely zero scientific information on this subject, but I'd definitely be interested in seeing some. I find this kind of stuff fascinating, and I really think it's often overlooked when discussing high fidelity audio and video equipment. Thanks,
The more direct source is from conversations Darin and I had with the folks at Brightside. At the time we were fighting the same misconceptions here on the forum about how little we could see instantaneously. At that time the popular number was 100:1, so at the very least it's nice to see the claims have creeped up to 200:1 or 300:1 or so, which we presented to the guys at Brightside who laughed at that idea. They quoted 100,000:1 instantaneous (5 orders of magnitude), and roughly 10^14:1 over time with full iris adaptation.
The closest text-source they have which mentions this is found here:http://www.brightsidetech.com/tech/p...ggraph2004.pdf
See section 3.
The eye can capture approximately 5 orders of magnitude
of dynamic range effectively simultaneously. No conventional display
technology comes close to this. Yet, there are limitations to
this capability as described below.
3.1 Local Contrast Perception
While we can see a vast dynamic range across a scene, we are unable
to see more than a small portion of it in small regions (corresponding
to small angles). Different researchers report different
values for the threshold past which we cannot make out high
contrast boundaries, but most agree that the maximum perceivable
contrast is somewhere around 150 : 1 [Vos 1984]. Scene contrast
boundaries above this threshold appear blurry and indistinct, and
the eye is unable to judge the relative magnitudes of the adjacent
Their HDR display has enormous on/off CR, and significantly greater dynamic range than any conventional display. In addition, they achieve something like 25,000:1 ANSI contrast (yes that's ANSI, not on/off).
If you google for "disability glare" you can find a variety of sources to journal articles that discuss the reduced CR range that we can see right at a high contrast boundary. This is important in real life, it's why stop lights have those big black borders around them, and why the entrance of a tunnel is lit more brightly than deeper into the tunnel for example, things which you'll find discussed in these studies.
Also, you can google for 'contrast sensitivity function' which is another source of confusion about the specific 100:1 number. CSF does not have to do with contrast range between black and white, instead it has to do with the Just Noticeable Difference, essentially bit-depth requirements to avoid visible banding. But some apparently have confused that and the 1.01:1 or 1:100 expression (1% JND) into a maximum visible CR range of 100:1 which of course is a completely erroneous interpretation.