Thanks. I posted my questions about using Contrast set so high a couple days ago but no one commented. Here's how I arrived at Contrast +25:Contrast is set way too high ... that's why the pic look over exposed. I experimented with CR at these levels initially. Then I got the a Sony 4K movie (e.g. Salt and Amazing Spider Man 2) where one can access the blk crush and wht clip test patterns by going to the disk menu (Play, settings) and enter "7669". Assume your projector Ypeak is at 100 nits, then set the white clip to 1000 nits ... assuming one does not have a spectroradiometer to measure luminance. Set blk level as well. One can fine tune these levels over time.
You'll see a bunch of color test patterns and after 3 minutes, use BR and CR to set the black level and white clipping level. These are what those patterns look like. These patterns are absolute values in nits (cd/m2) and are unique to HDR. Mouse over the pics to see each pic's description.
As far as using Dark Level, Bright Level and Picture Tone see. http://www.avsforum.com/forum/24-di...000-x7000-owners-thread-464.html#post46550833
- BT2020 color space, Tone +14, Bright/Dark +5
- Lamp high, iris -3
- 2.37 AR 140" wide, 0.95 gain, picture zoomed to show 2.40 movie at full screen = 14 ftL = 48 nits
- 48 x 10 = 480.
So with that said, I used the Amazing Spiderman 2 Sony patterns. I carefully evaluated the different contrast settings and what it took to clip at different ranges. To clip at 500 required Contrast of 25. I used mountain snow and cloudy skies to confirm that there we no or very little clipping at 25.
Unless I misunderstood something along the way then I am following the x10 procedure correctly? In which case +25 is what it takes to get Contrast set where it needs to be. I am quite certain that under that number the clipping level raises up. In fact I took some notes - let me see... At +18 the patterns clip at 700, +15 clip at 800, +12 clip at 900, At +28 clip at 400. At 0 clips at 1900 or 2000. +13 clips 1000, +7 at 1200, +3 at 1500 etc.
Based on this do you still think Contrast is set too high? I agree with you that the high contrast setting is causing it to look over exposed. But I am only following directions as to the x10 method. So either I am misunderstanding something or there is a big price to pay in terms of over exposure for trying to get the benefit of HDR, at least as it applies to my screen size?
Interesting. Please see my post to Carbon Ft Print directly above this response to you. What do you make of this?Cool Ric… now you're getting close (or could be already there as this will never be perfect given these PJ can't hit their mark for HDR spec). So it sounds like 14 is your sweet spot, now play with you White LvL w/ +5 as your baseline. Once you get it really close (and that is a great movie to use with all the intra-scene contrast like those base camp Mtn scenes showing sky, snow & dark rocks etc… pause on that and play around). This also assumes you already have your JVC settings right for Br/Ct (which it sounds like you do).
Not to concern you or anything but my JVC calibration is +10 for contrast w/ all others at 0 (sounds like you are using an enhanced Colorspace perhaps?)