Incorrect white level on Z2000 pro

Discussion in 'HDD Media player(RTD 1619BPD)' started by diginyu, Aug 30, 2023.

  1. diginyu

    diginyu New Member

    Does anyone expericing an incorrect white level on Z2000 pro?

    My HDR output is set to VS10 LLDV, everything looks too bright and over saturated, I've tried playing both SDR and HDR white clipping video, it shows a complete white screen without any black bar blinking.

    I've also experimented with the VS10 HDR option, it shows the same as LLDV's. However changing the HDR output to Auto solved the problem.

    My signal chain is Z2000 Pro > Vertex 2 > Optoma P2 projector, and I am using the 1000nits BT2020 LLDV EDID.

    Any advice would be greatly appreciated.
  2. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    No, white clip is pretty much spot on in all modes but you have to remember that with an HDR signal, white clip is defined by tone mapping so from what you describe it sounds like the gamma curve in the projector is way too aggressive (ie bright) and is therefore clipping the highlights.

    I'm not familiar with the Optoma, but I assume you're using the Vertex to send a custom HDR message like this rather than using a custom gamma:

  3. diginyu

    diginyu New Member

    Thanks for the info! Yes I am using the vertex to send the custom HDR message with the configs same as the screenshot you've attached. I've also forced the output in Zidoo to VS10 HDR to look at the OSD value and the webui value, but I don't know whether my custom HDR config is applied correctly. However the brightness issues appears with both VS10 LLDV and VS10 HDR setting.

    This is my setting and captured value from the webui, the OSD shows the same value as 500/0.005 nits, 0/0nits.
    Last edited: Aug 30, 2023
  4. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Yep - looks like the settings are correct.

    For HDR10 output, the OSD has MaxNits of 500 by default but if you play HDR10 content, MaxNits (MaxDML), MaxCLL and MaxFALL are taken from that content.

    Of course if you play in LLDV, the values are taken from the HDFury custom HDR settings above, ie MaxDML and MaxCLL 1000nits etc and this is matched by the values in the Dolby Block of the LLDV EDID (and you won't see that reported by the Vertex because it's receiving LLDV, not HDR10).

    So I'm not really sure what's going on here other than the projector not handling the HDR messages properly.

    I just tested SDR, HDR10 and Dolby Vision white clip patterns and clipping was correct on my display for VS10 HDR, VS10 LLDV and also Auto
  5. diginyu

    diginyu New Member

    I appreciate the explanation, it clear my doubt regarding the vertex 2 configs. I believe the vertex 2 and zidoo player is set with the correct configuration, and the problem should be caused by the projector itself.

    I've tried to play around the projector setting and found if I turn the "dynamic range" off in the graphic setting, the white level become much better than setting the option to "auto".

    Reading from the manual it said:
    • Auto: Auto detect HDR/HLG signal.
    • Off: Turn off HDR/HLG processing. When set to Off, the projector will NOT decode HDR/HLG content.

    With the setting turned off, shall I assume that the HDR content is processed by the zidoo and vertex 2 rather than the projector? Maybe the cause of the problem is the projector process HDR poorly than the zidoo? I can confirm that the vertex 2 TX0 is still otuputing 4K23.972 422 BT2020 12b HDR 297MHz.
  6. Markswift2003

    Markswift2003 Well-Known Member SUPER Administrator Beta test group Contributor

    Dynamic Range "Off" does not sound like a good idea - but what exactly "the projector will NOT decode HDR/HLG content" means I don't know - I don't know what it does instead.

    It may be that the projector is just not good at tone mapping, in which case it would be an idea to try letting the Zidoo do it by setting HDR to "VS10 Engine (Output SDR)" and set the projector into its SDR (Rec.709) mode.

    At the end of the day, no matter how expensive, any projector is always an SDR device because it can't get anywhere near the output required for true HDR so something has to tone map all the way down to the SDR domain (around 100nits) and whether it's the projector or the source, it depends which is the best at it.

    Certainly worth a try.
  7. diginyu

    diginyu New Member

    Great idea! I've tried the VS10 SDR + rec 709 option, the white level is way better than using HDR or LLDV. However overall the graphic is dimmer, especially noticeable during dark scenes.

    What puzzled me the most is none of the problems occur when I am using the Shield tv pro 2019 as the source. The black and white level of LLDV and HDR content works fine back then, but switching to the zidoo produced the problems.

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