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Merry Christmas!

Just so I'm following...

I understand that you have tried to find a way to use HDR because that will retain the most color saturation. But I'm wondering about your most recent best/compromise settings (70 nits) and contrast. I had inferred, or hoped, that while
your latest settings didn't get highlights as bright as your previous setting (100 nits), they were still brighter than you would get from SDR. In other words my question is: are you managing to get a somewhat more dynamic/contrasty image with your current HDR settings vs a regular SDR setting? Or are the only benefits you see related to color saturation?

I'm just hoping we could still get even a bit of the HDR contrast effect on our projector.
Consumer HDR was invented because bluray was mastered to a peak luminance of 100nits when flat panels had started to go up to 800-1000nits. For these panels, being able to keep the same reference white around 100nits and shoot highlights up to 1000nits+ means more dynamic range. That's because they have MORE dynamic range available than the former format offered (0-1000nits vs 0-100nits).

With our projectors, in a bat cave, we can't sustain much more than 50nits for reference white, so we were already remapping the 0-100nits of bluray to 0-50nits. BUT we have a great native contrast within that range, say 100,000:1 with our rs500 (it will be less or more depending on each set-up, but let's keep this as an artificial number for the discussion). With bluray, we're mapping 0-100nits into 0-50nits and we get 100,000:1 native on/off (at least twice as much with the DI). Our black levels, with a reference white of 50nits, are very low, thanks to the 100,000:1 native on/off.

The only thing we needed was the Dolby Vision cinema HDR which has reference white at 48nits and peak white at 108nits. But that will never happen, so no need to lament about that.

We have to deal with HDR content, mastered for flat panels (either OLED with deep black and 600nits or LED with no so good black but up to 1000nits). This means we have to map to the same reference white (it's not defined but it's around 100nits) to around 50nits, just the same. Anything more than that, at least in a bat cave, it too much for your eyes (too straining) if sustained over a long period of time. The question is what do we do with the highlights (anything above 100nits in the content, which we display at around 50nits anyway).

We can try to get up to around 150-200nits peak brightness (for those who can, we end up with significantly LESS native contrast, and a significantly ELEVATED black floor). So we'll still map 0-100nits into 0-50nits, and then we can compress 100-1000nits+ into whatever remains, say 50-150nits in most cases.

You have to realise that we're talking highlights. Most of the content is mastered EXACTLY as bluray, between 0-100nits (which end up between 0-50nits in our bat caves).

In order to map the highlights into 50-150nits, you have to open the iris (which LOWERS the native on/off) and for most of us use high lamp, which raises the black floor even more.

This means that we end up with LESS contrast, to try to show some elusive highlights (mostly specular highlights, chrome, sun effect, some bright lights etc). Chasing the highlights means killing the black floor and reducing the effective contrast, hence the dynamic range.

This is the main difference with panels. With panels, HDR allows you to use formerly unused dynamic range (the part between 100-1000nits). With projectors, it KILLs contrast. For example, if I open my iris fully to get around 200nits peak brightness in high lamp, my contrast drops from more than 100,000:1 to around 40,000:1, with a much higher black floor. HDR done the JVC way (high lamp, iris open) means LESS dynamic range, not more, at least for those who can display SDR with reference white at 50nits with the iris not fully open. The closer you can set the iris to reach around 50nits, the more dynamic range you gain.

This is why, instead of trying to chase highlights, we have two solutions to regain this lost dynamic range:

1) use SDR BT2020, which forgoes the highlights completely and converts say 0-1000nits (or more) to the usual 0-100nits, which we then display within our usual 0-50nits, with one main upside (return of the black floor and full native on/off, so MORE contrast than HDR) and one main downside, desaturation of the WCG (we might be getting a bit more than rec-709, but not that much and definitely not the full WCG that we're getting with HDR).

2) Go the other route I suggested recently, which is to keep HDR, so keep the full WCG, but map it into the configuration that gives us the most native on/off, so very close to our SDR settings. That way, you map the usual 0-100nits in the content (where most of the information lies anyway) into our 0-50nits, BUT we're using whatever we can get while still keeping a decent black floor to map the rest.

In my case, I use an iris setting of -13 in HDR instead of -14 in SDR, and I have reference white around 50nits and I use 50-70nits to display the highlights (100-1500nits as I clip around 1500nits to save brightness).

This compromise gives me:

- Black floor and low APL scene almost as good as what I get in SDR rec-709, I just lose the DI and my black floor is only slightly elevated.
- I get close to the native on/off I have in SDR, say around 90,000:1. Much better than the 40,000:1 I would get in JVC recommended SDR, and better than the 60,000:1 I would get with the iris at -7.
- Full BT2020 (at least the portion that's used at the moment, so around DCI), so more vibrant colors than rec-709 /BT2020, especially with high luminance parts of the pictures: sky is more blue, fire is more red, instead of being closer to white in SDR BT2020 and much closer to white in rec-709.
- The higher resolution of HDR, even through -eshift
- More highlights than in bluray, because in bluray most of the time there is nothing between 235 and 255, which with UHD Bluray we know that there is something above 100nits, even if it's not all the time and not most of the content.
- Much less banding than in bluray thanks to the 10bits color depth.
- Full immersive sound track (my main reason for upgrading at this stage given all the limitations in projectors)

Overall, it's not perfect, but I would call it SDR+ instead of what we get otherwise, which is HDR-. I think I'll need a Radiance Pro or Dolby Vision with the DI to be fully happy, because only this will allow us to keep all the benefits while keeping an accurate calibration, the full dynamic range our projectors are capable of and the black levels which are why many of us have bought a JVC.

The big difference with the Radiance Pro approach is that we can keep all the benefits of HDR without any of the drawbacks:

- We can decide how much we're ready to raise the black floor, which gives us our peak brightness. Because we get the DI back, we could choose to open the manual iris more than with my latest compromise.
- We can map the whole HDR content into this dynamic range using their shaping LUT.
- We can keep the DI because the Radiance converts to SDR before the PJ displays the content.
- Because the Radiance knows your peak white value, it can map the content much more precisely than the player can.
- You can adjust this mapping to your preference re where to clip as there is no standard to achieve that.
- You can calibrate accurately to known standards like BT2020 and BT1886 or power gamma 2.4.

This means in theory that we can get close to my last compromise, but with better calibration accuracy for both gamut and gamma, and we get the DI back, so near perfect fade to black (with more or less artifacts depending on how much you open the iris).

In the meantime, my latest compromise is the best I've found to date, despite the somewhat inaccurate calibration and the loss of the DI.

I realise it's counter-intuitive, but I hope the explanation above will help to explain why HDR on projectors without a DI active in HDR is kind of one step forward and two steps backward. My compromise gives one step forward and half a step backwards, which is still half a step forward :)

The thing that annoys me most, apart from the loss of the DI (I can live with that with the manual iris at -13) is the lack of accuracy in the HDR calibration. I can tune it to something that looks correct and that I like, but I'm not sure how accurate it is. I know it's not completely out of whack, but I have to lower dark gamma for example to prevent raising the black floor a little bit more than I'd like to. I'm not crushing black, but I know that as a result my low end is slightly too dark.

This "shooting in the dark" regarding calibration is what I hate most about HDR, but the PQ improvements vs SDR are too good to turn down, and that's without mentioning the AQ improvements (immersive track most of the time not present on the bluray).

My apologies for asking naive questions. Hope you won't mind me asking. What is DG? In Gamma D, I see Picture Tone (PT), Dark Level (DL) and Bright Level (BG). What's DG?
Also, can you please recommend what Contrast/Brightness need to be for Super White Input?
Thx and happy Holidays.
What I call DG is Dark Gamma, PT is Picture Tone and BG is Bright Gamma.
 

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The previous quote where I posted a screen shot from Pacific Rim shows I was able to pass 4K/24p 4:4:4 12 Bit, So to answer your question, Yes.

When I first hooked up my Panasonic I only had an older HDMI 1.3 cable
and it was not able to pass 4K at all, black screened.

I then hooked up the Panasonic direct to the JVC with the supplied short 6' 18Gbps
(That shipped with the Panasonic UB900) and it worked fine with the highest possible setting.'
I then used the old HDMI cable for audio only from the Panasonic to my AVR.
..only trouble with that was losing on-screen display from my AVR (GUI settings and Volume overlay).



So the next day I went shopping for a High Speed Active HDMI cable,
Guess I got lucky on my first try with the cheapest one I could find locally.

I would suggest that your issue may be the sync time delay on the JVC for HDMI
and that the signal test time of the Panasonic expires before the JVC passes 4:4:4,
You end up with the next step down because that's when the JVC finally makes full sync.

If you memorize the sequence for accepting the "Can you see at this resolution" prompt.
(I think it's a two step process, up and then enter, or left then enter)
You can tell the Panasonic "Yes" to the 4:4:4 setting even though the JVC has not finished the sync process and displayed the screen for it.

I did mine three months ago, so I can't recall exactly.

I do remember barely having enough time entering my response to accept 4:4:4 before it dropped to the next lower resolution.
Not even a full second.

If I had to go through the steps again setting up the Panny, I would just do it through my 4K OLED that has almost no delay when performing the HDMI handshake.

Sometimes it's a cable issue, sometimes it's the JVC HDMI sync delay taking longer
then the Panny resolution test, sometimes its a combo of getting past all three hurdles.

Hope that makes sense :confused:
Ok then I'm going to order one now. I did try your method to see if its a handshake issue but no success. I left if for 5 minutes and still had No input.

This is what I found from Amazon https://www.amazon.com/IOGEAR-Cable-Active-Redmere-GHDRC40/dp/B00I48Q892/ref=sr_1_1?ie=UTF8&qid=1482601604&sr=8-1&keywords=IOGear+High+Performance+HDMI+Cable+with+Ethernet%2C+40ft
It is active but it says in description that its a 10.2 Gbps cable. Shouldn't it be 18 Gbps? May be its not the one you had but I couldn't find yours with 18 Gbps.
 

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Thanks for posting this, it did enable me to get the 4:4:4 setting to lock in. However, I still can't get it to display BT2020 when feeding my JVC 750 projector. Do you think it still could be a cable issue?


Sent from my iPhone using Tapatalk
I have no idea what cables you have,
what settings you have on your player,
or if you've properly setup a 4K BT.2020 user slot on your JVC.

So it may be your cable, maybe your player or the JVC that's defective. :confused:
If you're using an AVR in the chain, that adds another device that may be the issue.

The Panasonic playback info display shows what signal it's reading off the disc, (line one)
and the outgoing signal being sent to the display (line three)
...are you sure you have the correct disc loaded?

Lot's of people mistakenly grab the first disc out of the 4K/BD combo pack
and don't even realize they left the 4K version in case.

...Okay I'll admit I've done this at least once too,
as not all studios place the 4K on the right side,
sometimes its on the left hidden under all the inserts :eek:
 

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Ok then I'm going to order one now. I did try your method to see if its a handshake issue but no success. I left if for 5 minutes and still had No input.

This is what I found from Amazon https://www.amazon.com/IOGEAR-Cable-Active-Redmere-GHDRC40/dp/B00I48Q892/ref=sr_1_1?ie=UTF8&qid=1482601604&sr=8-1&keywords=IOGear+High+Performance+HDMI+Cable+with+Ethernet%2C+40ft
It is active but it says in description that its a 10.2 Gbps cable. Shouldn't it be 18 Gbps? May be its not the one you had but I couldn't find yours with 18 Gbps.
You don't need 18Gbps, but 10.2 is NOT enough to pass 24P 4:4:4 12Bit

That needs at least 13.4Gbps


You can't wait 5 minutes,
You need to make the selection within 5 seconds,
whether you can see anything on the screen or not.

Then load a 4K disc and wait as long as it takes.

:)
 

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I have no idea what cables you have,

what settings you have on your player,

or if you've properly setup a 4K BT.2020 user slot on your JVC.



So it may be your cable, maybe your player or the JVC that's defective. :confused:

If you're using an AVR in the chain, that adds another device that may be the issue.



The Panasonic playback info display shows what signal it's reading off the disc, (line one)

and the outgoing signal being sent to the display (line three)

...are you sure you have the correct disc loaded?



Lot's of people mistakenly grab the first disc out of the 4K/BD combo pack

and don't even realize they left the 4K version in case.



...Okay I'll admit I've done this at least once too,

as not all studios place the 4K on the right side,

sometimes its on the left hidden under all the inserts :eek:


Thanks for the Christmas gift! I am too stupid to live! I was mistakenly running the 1080p version! Awesome picture now, with BT2020! Wish I could get back the lost hours fooling with this.


Sent from my iPhone using Tapatalk
 

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You don't need 18Gbps, but 10.2 is NOT enough to pass 24P 4:4:4 12Bit

That needs at least 13.4Gbps


You can't wait 5 minutes,
You need to make the selection within 5 seconds,
whether you can see anything on the screen or not.

Then load a 4K disc and wait as long as it takes.

:)
Ok then the one I linked is not your cable. I searched it my name and could only find two matches (1 with 40, 2nd with 60 ft).
I didn't wait 5 minutes to press Yes. I waited 5 minutes after pressing Yes to see if projector can detect. Will try one more time.

Update: tried it again and no luck. Its my cable. Now I need to find one that is 20 feet long and has at least 13.4 Gbps active HDMI.
Update 2: Ordered this https://www.amazon.com/dp/B016KOPSHE/ref=twister_B01BOH3414?_encoding=UTF8&psc=1
 

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Thanks for the Christmas gift! I am too stupid to live! I was mistakenly running the 1080p version! Awesome picture now, with BT2020! Wish I could get back the lost hours fooling with this.


Sent from my iPhone using Tapatalk
LOL!

Success!

I finally got something right, thought I was going to lose my mind!

Cheers'
 

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Thanks for the Christmas gift! I am too stupid to live! I was mistakenly running the 1080p version! Awesome picture now, with BT2020! Wish I could get back the lost hours fooling with this.
I would have lied and said it was a cable... :D:cool:

good to hear you found the issue
 

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Do you mind connection HDMI to Panny directly and see if it can detect 4k/60 (4:4:4) using Setup --> 4k60P Output? In my case it says No input with my current HDMI for 4K/60 (4:4:4) and pbicks up 4k/60p(4:2:0). That's what I have as of now. When playing HDR, using playback info, I see HDR/BT.2020 YCbCr 4:2:2/12bit. First, I don't even have BT 2020 on my projector so that's misleading. Secondly, I'm not getting 4:4:4/12 bit but 4:2:2/12 bit. Hence my search for HDMI.
Thanks.
I had to go back a few posts,

THIS (in Bold) may be the root of all your problems
and the one thing that separates your issues from all others.
IMHO, Fix that first!

There is also virtually no distinct visual difference from 4:4:4/12Bit to 4:2:2/12Bit
as ALL Current Native 4K/UHD discs are 4K/24p BT.2020 4:2:0 10 Bit, period.

However that is not a valid format for HDMI, (see the chart posted previously)
so it MUST be converted in the player to 4:4:4 or 4:2:2

If you're getting BT.2020 4:2:2 12-Bit,
it's already spec'd higher than what's on the disc

I used 4:2:2 12Bit for the first month and didn't see any difference at all:


...IMHO, leave well enough alone and just enjoy the movie
But for crying out loud, load the BT.2020 profile to your JVC FIRST
or its all completely moot!

Peace Out :D
 

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X750 focus

Hey folks...

Is there any other trick or pattern to focus the x750 any better than using the green pattern under the focus menu? Doesn't seem very refined to me...thanks folks...
 

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Hey folks...

Is there any other trick or pattern to focus the x750 any better than using the green pattern under the focus menu? Doesn't seem very refined to me...thanks folks...
Put any text on screen (turn e-shift off) and use the settings menu
instead of the lens control button on the remote.
 

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Put any text on screen (turn e-shift off) and use the settings menu
instead of the lens control button on the remote.
Thanks, specifically, what settings menu? Trust me I did look :)
 

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You don't need 18Gbps, but 10.2 is NOT enough to pass 24P 4:4:4 12Bit

That needs at least 13.4Gbps


You can't wait 5 minutes,
You need to make the selection within 5 seconds,
whether you can see anything on the screen or not.

Then load a 4K disc and wait as long as it takes.

Ok then the one I linked is not your cable. I searched it my name and could only find two matches (1 with 40, 2nd with 60 ft).
I didn't wait 5 minutes to press Yes. I waited 5 minutes after pressing Yes to see if projector can detect. Will try one more time.

Update: tried it again and no luck. Its my cable. Now I need to find one that is 20 feet long and has at least 13.4 Gbps active HDMI.
Update 2: Ordered this https://www.amazon.com/dp/B016KOPSHE/ref=twister_B01BOH3414?_encoding=UTF8&psc=1
I have tried a blue jeans 1e 20 foot certified and a monoprice certified and both work at 20 feet. Just my experience so for but with a Rs400
 

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Is there any other trick or pattern to focus the x750 any better than using the green pattern under the focus menu? Doesn't seem very refined to me...thanks folks...
You will have to turn off the green pattern and display a focusing screen that you supply yourself.
 

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Thanks, specifically, what settings menu? Trust me I did look :)
Seriously?

First hit Menu

and turn off e-shift (this allows you to see the pixels)


Installation Menu

First selection is lens control


Turn image pattern to off


Change lens control to Focus


Now get off your arse and walk up to the side of the screen.
The up-down motion on the direction/cursor keys of the remote adjusts the focus
With e-shift off you should be able to tell when the pixel structure is at it's sharpest
while looking at white text on a darker colored background.
 

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Seriously?

First hit Menu

and turn off e-shift (this allows you to see the pixels)


Installation Menu

First selection is lens control


Turn image pattern to off


Change lens control to Focus


Now get off your arse and walk up to the side of the screen.
The up-down motion on the direction/cursor keys of the remote adjusts the focus
With e-shift off you should be able to tell when the pixel structure is at it's sharpest
while looking at white text on a darker colored background.
Perrrrrrfect, thanks man...
 
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How to force a 3D move to play in 2D?

Hey guys - I have a 3D only Blu-ray but don't have enough glasses for all guests, so I need to show it in 2D. Is there a way I can force the JVC to show it in 2D? I realize it would be at half the resolution, but that's ok for this purpose. The source is "1080p24 FP". I tried changing the JVC 3D Menu from Auto to 2D. However the projector is still showing both L and R eye images even though 2D is selected in the menu. Hence it is unwatchable without the glasses. Any ideas how to do this? Thanks!
 

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Hey guys - I have a 3D only Blu-ray but don't have enough glasses for all guests, so I need to show it in 2D. Is there a way I can force the JVC to show it in 2D? I realize it would be at half the resolution, but that's ok for this purpose. The source is "1080p24 FP". I tried changing the JVC 3D Menu from Auto to 2D. However the projector is still showing both L and R eye images even though 2D is selected in the menu. Hence it is unwatchable without the glasses. Any ideas how to do this? Thanks!
Try setting the player to 2d.
 
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