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But if you have the UB9000, and a PJ calibrated for regular HD/SDR content, then what you should do is utilize the HDR Optimizer and SDR conversion capabilities of the Panny which takes care of the EOTF portion of things. No need to mess with Gamma D or custom curves, let the UB9000 handle all that, it's really really good at it.
What is EOTF?
 

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What is EOTF?
EOTF = electro-optical transfer function

It's the technical term for what people are talking about when they say things like "tone mapping" and "custom gamma". It's the function that transfers/maps the full luminance range of the HDR signal to the capabilities of the display.

So for example the HDR content may be mastered at 1000 nits peak brightness, but the projector can only do 150 nits peak brightness off the screen. Somehow you have to translate the full dynamic range of the HDR signal to the lesser range of the projector.

One option is to just squish it all in with a direct linear transfer, but that will result in a very dark image since squeezing in all the dynamic range of the highlights will necessarily compress all the mid/shadow detail too (this is why many people complain that HDR looks too dark, and probably similar to what Gamma D does).

Alternately a custom EOTF curve, whether programmed by a calibrator or done automatically in the player or display, will "shape" it more intelligently to preserve the dynamic range of the shadows and middle regions and then roll things off more steeply in the highlights. So the image doesn't look dark and gross but you still maintain some detail in the specular highlights regions. The "HDR brightness" slider control you'll see on many players and displays basically changes the shape of this transfer function, but it will be a compromise in one direction or the other. If you try to preserve more highlight detail, then by definition you'll have to squish the dark/mid areas of the image down so the overall image will look darker. If you want the overall image to be brighter, then the inherent trade-off will be losing some of the detail in the highlights.
 

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I recently ordered a Panasonic DP-UB820-K Blu-ray player, based on advice posted in this thread. I'm looking for further advice! How should I hook this up? With a long HDMI cable directly to the projector? Or can I go through my Yamaha RX-V679 receiver?
I've a Costco Yamaha TSR-7850, same Panny 820 going into a JVC RS500, with a high speed certified HDMI cable. Make sure all the interconnects are also high speed; do not skimp on cables. I use Monoprice as Dreamliner recommended, who has been very helpful in the tone mapping and setup.

Shoot me a mail if you need assistance on the Yammy.
 

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But if you have the UB9000, and a PJ calibrated for regular HD/SDR content, then what you should do is utilize the HDR Optimizer and SDR conversion capabilities of the Panny which takes care of the EOTF portion of things. No need to mess with Gamma D or custom curves, let the UB9000 handle all that, it's really really good at it.

Set the UB9000 to output SDR with Rec.2020 color. Use your calibrated SDR settings except switch the color space to Rec.2020 instead of Rec.709, and it should be as close to optimal as you're going to get.
I have tried all your suggestions without much luck
Maybe it's just a movie with bad PQ?
Usually bright outdoor scenes look amazing in 4K HDR... but on The Meg UHD they do not look good
Darker scenes in the movie look a lot better
I just don't can't find a mention of this problem in reviews
 

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I have tried all your suggestions without much luck
Maybe it's just a movie with bad PQ?
Usually bright outdoor scenes look amazing in 4K HDR... but on The Meg UHD they do not look good
Darker scenes in the movie look a lot better
I just don't can't find a mention of this problem in reviews
Reviews rarely mention real problems (Disney Atmos for example). The RS400 has a real finicky "HDR" system. It is also possible the disc PQ is bad but usually when I hear people complaining about "certain titles", it's because they are not using SDR2020. It is exactly what I went though.

Did you try following my Panasonic/JVC Guide (clicky)? The settings should be almost identical on the UB9000.

You either need to follow my guides for a baseline or list out every single video setting on your UB9000 and RS400 so we can see what is wrong.
 

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Dreamliner, I followed your directions and it looks good
But by choosing SDR/2020 on the Pana UB9000 do I miss out on HDR?
People seem to think that HDR is more important than the higher resolution... and I would have to agree
My JVC X5000 is fake 4K, after all
 

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Dreamliner, I followed your directions and it looks good
But by choosing SDR/2020 on the Pana UB9000 do I miss out on HDR?
People seem to think that HDR is more important than the higher resolution... and I would have to agree
My JVC X5000 is fake 4K, after all
The naming of SDR/2020 gets confusing, it's still HDR. Here's the background:

all projectors require some form of tone mapping with HDR content. it either occurs at the source (Panasonic UB820/9000) or at the projector itself with it's built in HDR curve or a custom uploaded curve. The goal is still the same and the Panasonic does an excellent job, especially when compared to JVC's first attempt (Gamma D) and even later version of it on the 420/440 models.

There are several advantages letting the Panasonic doe the tone mapping. It can select a specific curve based on meta data that is sometimes present on UHD titles. If a specific title doesn't have that data, it defaults to a standard curve that is still quite good. It also allows the projector to use the DI with HDR content with the SDR/BT2020 mode.

The next level of HDR tone mapping is with an HTPC + MadVR which allows for dynamic tone mapping. a process where the software is constantly adjusting for optimal visual appearance per scene. Ideally one day projectors will have this built in, but today it requires a powerful graphics card to handle this kind of constantly changing workload throughout the movie.

For those that want set it and forget it, the UB820/9000 tone mapping is a blessing that would have been welcome if it was released several years ago when the JVC's first released this series with HDR capability. Better late than never :)
 

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Thanks for clearing that up
Watched another UHD movie… it looked very good, hard to see how it could look much better :)
Unless I win the lottery and get the JVC 4K laser PJ (can't recall model name right now)
 

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Projector issue, when I try and power on the standby light goes solid, bulb lights up, DILA on screen, then shuts off and standby light blinks until powers off. Tried cleaning filter, removing and reinserting bulb and plug and unplug no change? Is this fixable or am I screwed?
 

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I would try a new bulb if you can get one from a place that allows returns. It sounds like the projector's ballast is sending an error code as the bulb starts to get into the final stages of warming up. There is a very sophisticated series of electrical phases that happens with projector bulbs as they are warming up and shutting down. Could be a lot of other things though as well, could be a bad FAN or a bad ballast. Eliminate a potential faulty bulb first.

If you can get into the projector menu before the projector shuts off (sounds like you cannot), but if you can, there are a couple other things you can try. The first is to quickly set the bulb to High lamp mode and see if that helps bypass the issue, also set the PJ to High Alt mode, and finally the last step is go into the service menu and check that all the FAN RPM's are ok and that there are no active error codes anywhere.
 

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We had a bad storm recently, just noticed two other things not working so I think that did it. What would that have likely damaged?
 

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Does the 820 play Atmos on Netflix? I've read where it does, but mine does not as far as I can tell.
 

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Does the 820 play Atmos on Netflix? I've read where it does, but mine does not as far as I can tell.
It is possible, but works with some AVR's and electronics, and not with others.

The UB-820 is not *officially* listed as supporting Atmos as a device, by Netflix, and yet many of us do in fact get it. I have a Marantz SR7010, and it gives me 4k/HDR and Atmos when available. A friend had a somewhat older Yamaha AVR and didn't get Atmos, but when he upgraded to a newer model, he did.
 
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