Originally Posted by tioneb
Thank you for the lengthy response, but I still need some clarification. By the way, you're right, it's the colour profile that determines whether the filter is on or not; I had forgotten about it.
I think we both want the same set-up. At the moment with the UB820, I use the filter for both SDR and HDR disks (User 3 for SDR and User 5 for HDR (with UB820 outputting SDR2020)) And I intend to keep that way with the Radiance Pro (so I can use the wider WCG ... my light output is OK with the filter on). However, I use different iris positions for SDR and HDR. I have the harmony hub and I can always set the power-off and power-on conditions. But I will discuss the issue with the iris position later.
I always knew that I wanted to set SDR2020 for HDR disks. So, I believed that the Radiance Pro should not send the HDR flag to the projector (b/c if it did, it would remove the filter automatically). But the following instructions on Radiance Pro manual on p. 16 threw me off: "Set the CMS-1 -> Colorspace -> HDR Flag to off for CMS1" So far that's what I thought I should do, but then it continues ... "unless you have a JVC projector you can select the HDR Flag = On in CMS1, to select a different projector memory for HDR than is used for SDR". Now that threw me off big time. Because the way I think the projector works (and I may be wrong) is that if it sees a HDR flag, it will automatically goes to a HDR picture mode removing the filter in the process. But I do not want the projector to remove the filter. So my question to you is: when you use the Radiance Pro with the RS540, do you set CMS-1 -> Colorspace -> HDR Flag to OFF or ON?
If you set it OFF, then I can a User Picture Mode and set the Color Profile to BT.202, Color Temp to HDR, Gamma to Custom (gamma 2.4), etc ...
But if I set it to ON, will it not put the projector in HDR Picture Mode (with the filter removed)?
Second, regarding the iris position, if I understand correctly, should I make sure that the projector upon powering up and powering down be always set to the same Picture Mode so that the iris position is always at the same position upon powering up and powering down? At the moment, the iris is always at the same position (manual -5) upon powering up and down; after watching a HDR disk (which uses a different iris position than for SDR disks), I always put it back to my SDR setting (with iris position manual -5) before powering down the projector. Is that what you have in mind to minimize iris malfunction? By the way, if my iris is malfunctioning and does not go to the iris position that I set in the projector menu, is there any way to find out about it?
Thank you (and also giomania) for helping me.
I would not use the HDR flag for the two reasons mentioned - lack of access to user / profile off, and issues with the iris. Not being able to use the WCG filter is not a reason to not use it.
You can have the filter on with the HDR flag operating. When you play some HDR you switch to BT2020 profile instead of HDR. BT2020 is an allowed profile for HDR flag operation. So then your HDR flag with keep the filter in. But you won't have access to a user profile.
Perhaps the manual is worded a bit strong (I've not looked at the wording). There's nothing forcing you to use the HDR flag with a JVC projector, it is a suggested way of operating, manufacturer recommended
. I'm suggesting a different way, but lots of folk use it successfully I'm sure (probably more dilligent than my lot are about power sequence and shutting stuff down in orderly fashion...).
If you are always powering up and down at the same iris position / mode you should be fine. It is only if you power up and down with content that would trigger the different modes via the HDR flag, and they have different iris settings, that you might have issues. In my case it is totally repeatable. To break it, set HDRflag to have iris 0, SDR to have iris -10, power off in HDRflag and then power up with SDR. You won't hear the lamp iris move from the 0 position back to -10, but the menus will think it is at -10 if you look (note, only the lamp iris seems affected, which is the really loud one that sounds like someone grinding coffee overhead...
). If you now try to play some HDR it is very obvious that something has gone wrong because the projector tries to advance the lamp iris from -10 to 0 (but it is already at 0) so it hits the mechanical end of travel and grinds (even louder).