I bought some test patterns from DVS yesterday for both HDR10 and DV with a view to calibrating my TV and PJ. I only made a quick start on DV to test the black level and it would not allow me to see the below 3.5% bars on the black level slide no matter what I did to the TV's brightness control. I played the black level slide in HDR10 and that worked fine and I was able to adjust it to get the right bars flashing down to 0% (ref black). Is this a known problem with outputting DV. I assume then that this is happening on all DV content.
No. not at all, I use R. Masciolla's test patterns and Dolby Vision resolves down to black 64 and white 723 for a 1000nit test pattern which is spot on. (I'll double check that at some point today - these tests were carried out some time ago)
The 35 usd pattern from here? https://www.diversifiedvideosolutions.com/products.html I'd be interested in testing this also, as I find the Dolby Vision image on my CX to be quite dark
I bought it and according to the documentation, when doing the basic black clipping test with "01. Black Clipping_1_Dolby_Vision.mp4" my TV should "show bar 4 (1.26% / 12) barely flashing" however for me it is only at bar 10 (3,5% / 36) that I can perceive the flashing. Is there anything I can do to mitigate this? I'm on an LG CX.
First thing is to make sure you're testing this in a completely darkened room - the problem with PQ gamma is that the signal comes out of black slowly compared to power gamma so down at the bottom end it's really difficult to perceive the differences and in daylight that can be pretty much impossible to differentiate.
Sorry - I was mistaken - the test patterns I'm using are the HDR10 ones converted to LLDV in the Zidoo. I didn't bother with the Dolby Vision ones because they're Profile 5 not Profile 7 - not that it matters for calibration, but I'm waiting for Stacey Spears to release their test disc.
Ok, I also found a Pluge test in Profile 5 Dolby Vision and tried that and was able to see all 5 above black grades so it's not the Zidoo that's crushing black. I don't have an LG TV but there does seem to be a whole lot of noise on the AV Forums about LGs and black level...
Exactly the same as me. Same min pattern showing (3.5%) and same TV. Haven't ruled out the TV obviously doing something strange, need to have a play.
From reading a bit into this, it seems that the CX is simply tuned in a way where there is near black crush out of box and there really isn't much one can do about that. Sony tunes the panel a bit differently to where that apparently doesn't happen as much, so there's that to keep in mind for when you buy your next TV I guess.
I have definitely had the impression of an overall dark presentation when watching DV content, it's the reason I came to this topic.
It appears the black crush is a bit less significant when using HDR rather than DV, is there a way I can force the Z9X to use the HDR10 "fallback" track? This is something that's part of most (all?) videos with Dolby Vision.
