Hey all, got my DLA-RS540 (7900/790) yesterday, and have discovered a crazy issue with the Dynamic Iris:
I'm copying/pasting this info from another forum where I posted it:
I've found with the Dynamic Iris set to Auto 1 or 2, I'm getting this very peculiar image glitch that completely destroys e.g. facial details.
It does this in SDR or HDR, and I'm using The Greatest Showman at min 48:59. It's easy to test. Just go to 48:59, and then just pause the movie, and make sure no other menus etc are visible. You'll notice (pause or unpaused) that Hugh Jackman's face does this weird contrast thing... I can't even explain it. Again, does this in both SDR and HDR, and the only way I've found to fix it is to NOT use the Dynamic Iris - just set it to manual.
When I bring up the JVC Menu, this issue disappears - I'm guessing because it disables the Dynamic Iris in the menus?
Either way, I'm really not happy about this.
Video:
Imgur
*edit*
If I set the iris to manual and set it to ~-10, and THEN switch back to Auto Iris 1 or 2, this seems to mitigate the issue. But if I set the iris to a number higher (I.e. -9 or above with DI enabled,, I see the issue get progressively worse the higher the number. What am I missing?) Why does manual DI take precedence over Auto?
What I'm seeing is a bug in how the Dynamic Iris automatically adjusts gamma/colors/contrast (something to that effect), depending on content on screen. The Greatest Showman (either Blu-ray or UHD) exhibits this really easily - and it's simple to reproduce yourself.
I took an exposure-locked screenshot with my iPhone X to show everyone the difference between DI ON and DI OFF. I really feel like the Dynamic Iris is pointless on these projectors. Sure, there may not be many instances in content where this issue occurs - but it's going to bug me knowing it COULD occur on any content. So DI needs to stay off, where this BUG (and to me it's absolutely a bug) doesn't occur.
Dynamic Iris OFF (note especially the horizontal crease in Jackman's shirt):
Dynamic Iris ON:
Bottom line: If you own the JVC 540/640 (can't speak for the 440), and you want to enjoy The Greatest Showman in SDR or HDR, be sure to watch it with the Dynamic Iris off. It's insane to me that I even have to type this.
For reference: I confirmed this issue with a 990 owner, too, after pointing it out to him to test.