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So I did some testing after creating a gamma curve using Arve's tool. I used settings similar to that of brian_vh....

1. 500
2. 100
3. 350
4. 4000
5. 0.7
6. 0
7. 1

Again I am using a 130" wide Seymour XD screen, 16ft throw, 9.4 gain.

My goal was to get 'outterspace' black levels comparable in Rec709 and HDR2020. So I fired up the martian and looked for some deep space scenes. I went into my testing with the expectation I would try several different curves. Quite honestly, I could not tell the difference between the black space presented in REC709 (scaled to 4K using MadVr) and UHD presentation.

However, I think I am beginning to see what people mean by 'spectral highlights' ... If you seek to 1:33:00 in the movie, you catch a little of the spaceship docking with supplies, then flying away form earth.

In this shot, space isn't pure black-- there is a soft glow of planet earth blue in both SDR709 and HDR2020, but what I really noticed were the highlights/reflections/lights whatever on the spaceship leaving earth. The UHD version highlights just pop with bright-blue running lights and gold reflections off of the solar panels. On the SDR709 playback, these features just kind of blend in and are not as pronounced.

I'm off to watch Lucy and some Better Call Saul now :)
 
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@Manni01, thank you so much for all of your hard work. I have followed your advice and I have a wonderful HDR presentation in my dedicated theater room...even my wife noticed! I have my Oppo set to Split A/V...

Oppo 203>Linker>JVC RS400. JVC 800-600-4000 custom curve loaded with the Oppo set to BR:+5 CN:-4.
JVC set to BR:0 - CN:0 - Lamp:High - Auto:2 - Iris:-5...100IRE pattern reads 112 nits.
Seymour AV Center Stage XD AT Screen: 130" wide (141" diagonal) 2.35:1 AR and 16' throw in a completely black room.

My son and his family live just outside London and I need to buy you several adult beverages on my next visit!! :)
 

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I did test it again and it doesn't seem to be an issue now. Don't know what changed, but it works the same with a Manni curve or doing a curve via Arve's tool.

So far I would say if you are using just the standard HDR modes of the projector than the 2017 is a much better projector. The default is quite good and the fact that it has a full user mode for HDR is icing on the cake. This also makes it easier for using the custom gamma curves as the user mode is fully customizable, so once you select your gamma it stays there (no worries about it going back to gamma D). But in terms of what gamma to use, the custom modes are more ideal as you have more control over the curve for calibration and more flexibility for multiple curves if you want. The only downside is the autocal doesn't work for the new models properly, but hopefully they will resolve this.

I am starting on my 3D evaluations this morning.
Like stevenjw said, you need a Linker to really get the best PQ out of the HDR whether its a 2017 JVC model or not The brighter your image the more that would likely apply.
 

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Hi Ric,

First you'll see little difference with titles mastered to 1000-1100nits. Second that's not the only thing you have to do. You also have to shape the curve to achieve what we mentioned earlier (fit the 0-100nits in the content that used to fit into 0-50nits in SDR BT2020 into 0-x nits, and fit 100-1100nits (or 100-4000nits depending where you clip) into x-50nits. As you can see, that's no easy feat and it will take time to achieve this in such a way that it looks better than SDR BT2020 with the slider to -5. It's doable but you're in for a long experimentation... Of course I don't know what x should be so that you get some benefit from the highlights without making the overall picture too dim.
That makes sense. I don't mind investing tons of time experimenting to find the best custom curve. The real challenge is I have no idea how to go about trying to fit the 0-50 nits into 0-x nits and the 100-1000+ nits into x-50 nits. I would literally be just randomly trying parameters in Arve's tool. Is there some way to interpret the Plot to see how my custom curve would map that? Any tips for figuring this out?

BTW, when you talk about measuring nits to see what your pj's potential is for HDR - like when you say ideally one should have 100 nits - is that peak white measurement supposed to be done with contrast at 0 or AFTER contrast has been adjusted down so that you clip at 4000?

Side note: Somehow over the past few months I totally overlooked at the slider on the UB900 should be at - 5 or -6 for SDR BT2020. So all the viewing I did in that mode until recently was with the slider at 0. The other day when watching Pan SDR2020 I tried the slider and found -6 was too dark, and settled on around -3. It looked nice, but was still a bit dim.
 

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I don't know wha the x500R was like BUT the procedure still requires serial cables, a windows computer (virtual machine works too) and following the sequence of what to power on when, and when to run the app, etc, very closely.

So probably no more simple than before.
So you still have to do the Flashmagic thing and then the download? Still quite antiquated and over complicated. No wonder I haven't done it yet.:(
 

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Here's a scene I THINK has spectral highlights. I can't really tell for sure because I can't get much benefit from HDR to know. :)

If you have Lucy, you can check this - spoiler alert:

In Lucy near the very end she turns herself into a mountain of black material. Extended at the end of this mountain of black material is a black USB stick that Morgan Freeman takes. Inside the black area of this USB stick there is a field of white star-like pixels swarming around. You can see it as the USB drive is extended out to him and as he studies it and turns it around. These "sparklies" seem to jump off the screen - sort of 3D like and seem to have a lot of brightness to them. When I watched at 16:9 (not zoomed) the effect seemed greater than when I watched zoomed for 2.40, giving further credence to the idea that indeed this is a HDR spectral highlight (because I'm starving for nits so it makes sense I would have seen this effect greater at the smaller screen size, which I did).

Also I imagine there is a HDR thread here on AVS where people are talking about HDR effects in movies and great examples. I have to run out now for a bit but if you have time to look around that would be great - let us know if you find such a thread and please link to it here if you have a chance. Otherwise I'll poke around later today.
Just finished up Lucy. Man what a ride. The picture was just stunning, deep colors, and the opening scene with the 'Lucy' ape in the water. Really happy with the PQ I'll just leave it there.

I dont think we even noticed the sparklies at the end scene when we first viewed it on my plasma. Pronounced and crisp is how wifey described it. I was happy just to see them at all :D
 

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Oppo 203>Linker>JVC RS400. JVC 800-600-4000 custom curve loaded with the Oppo set to BR:+5 CN:-4.
JVC set to BR:0 - CN:0 - Lamp:High - Auto:2 - Iris:-5...100IRE pattern reads 112 nits.
Seymour AV Center Stage XD AT Screen: 130" wide (141" diagonal) 2.35:1 AR and 16' throw in a completely black room.

My son and his family live just outside London and I need to buy you several adult beverages on my next visit!! :)
So I have the exact same setup except with an rs600 and only getting about 80 nits. I must be doing something wrong.

:confused:
 

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Question regarding 3D: I calibrated my RS500 with autocal. I am using 709NF color profile with normal gamma for the blurays. Question is: what should I use for 3D. Is there a separate calibration method for 3D?

Also, I am using AVSForum disc for basic settings (BR and CR). How do I use it for 3D (assuming with glasses on).
 

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Normally for a video mode to exist as a standard resolution it must have a VIC (Video Identification Code).
But there isn't any for 4K24/25/30 4:2:2 deepcolor

So don't be surprised if some companies have issue with supporting it and some equipment issue with detecting it. Trust your eyes ;)
Thanks for the valuable information.

So it is entirely possible for the Oppo to send at 4K24 4:2:2 8/10 bits? Since there is no VIC for this mode the JVC reports it as 12 bits?

If one looks at the INFO screen on the Oppo it does state it is sending 8 bits or 10bits. However, does not the JVC have to have 4K24 4:2:2 8/10 bits "registered" in its EDID to allow it to be sent?

All very confusing.:confused:

OTOH if one selects a mode that is impossible to send (e.g., 4K60 4:4:4 12 bits) the Oppo will correct it. This can also be seen on the INFO screen.

If one wants to do the conversions outside the player or limit the bandwidth used for transmission, 8/10 bits can be useful.
 

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Humm, where did all my lumens go??

So I have the exact same setup except with an rs600ad only getting about 80 nits. I must be doing something wrong.

:confused:
You guys have me wondering how my lumens are so low.... My screen is the same as yours except just 10" wider. Center Stage XD 140" 2.37AR. I can't see how 10" bigger means my lumens would be almost half yours (I'm around 45 nits).

I know the JVC bulbs are supposed to be really good as far as losing brightness slowly goes. Now I'm starting to wonder if something is wrong with my bulb or setup, because it should be much brighter.

I'm looking at my notes for when I first set up the pj in October 2016. It says that on high with iris fully open and pj zoomed to fill a 2.37 image (no bars) I was getting 194 lux calibrated, 68 cd/m2. That should be close to 60 nits instead of my 45. That measurement was without the filter so I just rechecked it and I get 130 lux. I have about 700 hours on my bulb. That's a drop of 30%. That doesn't make any sense for the newer JVC bulbs, does it? This is Calibrated lumens. If I reset my RGB gains (-20 red, -18 green, 0 blue) to be 0 I measure 145 lux. But at any rate my notes say my 194 lux was at D65.

As a side note, I set my zoom to 16:9 and took a few measurements just now. 204 lux in BT2020, 218 lux Rec709NF, 243 lux Rec709NF with 6500K color temp and zeros in RGB gains/offsets.

I think the spec on the RS500 is like 1700 lumens. Is that CALIBRATED lumens? My throw is about 20 feet so I'm probably losing about 20% due to that. But something isn't quite adding up.

Is it possible my lumens have dropped this much? Could my bulb be an issue?

Thanks!
 

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Got my i1d3 meter out last night and put up a 100IRE pattern to measure my max ftL.

With my X750R zoomed out to 138" diagonal scope screen, lamp on high, Iris at 0, and Gamma on autocal'd Normal setting, I measure 29 ftL.
Screen is a Dalite 1.3 gain JKP (and is true 1.3 gain material).

Three questions:
1. Is leaving the Gamma at Normal correct, or should I be using Gamma D or one of Manni's curves?

2. If it's true I'm getting max 29ftL, that's 99 nits. So is it worth it pursuing HDR (creating custom curves, buying HDR disks, Linker purchase, etc.)?

3. If worth it, what curve should I start with in Arve's tool?

I really don't like running in high lamp. I get 70 nits in low lamp with Iris fully opened. Likely not bright enough though I'm thinking right?
Just a quick update on this: I squeezed a few more ftL by switching my BT2020 profile to Manni's BT2020NF one. Any thoughts on my other questions above?
 

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So I have the exact same setup except with an rs600 and only getting about 80 nits. I must be doing something wrong.

:confused:
I am using an i1Display Pro meter that Chad B profiled for me when he was here last December and I have the latest Calman software so I think the number is good...it sure is bright to my eyes! I will be very interested in your results after a Chad B calibration...make sure you have him do a 3D calibration - his settings are pure magic!

:)
 

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I downloaded one of the Manni Gamma curves and installed. 140-1100-4000 V2 I must be doing something wrong as I must be the only one who thinks Gamma D looks better. :eek:
 

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Like stevenjw said, you need a Linker to really get the best PQ out of the HDR whether its a 2017 JVC model or not The brighter your image the more that would likely apply.
Don't really agree here, I think it falls on each person's setup. I am using high lamp with the iris at -6. I find the black levels to be absolutely fantastic without the DI needed. There may be some really dark movies that may benefit, but for now I don't see any need for it in my setup. I don't like how it truncates the brighter whites at times for a marginal improvement in black that would already be perceived better from the biasing the brighter whites would have provided.
 

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Question regarding 3D: I calibrated my RS500 with autocal. I am using 709NF color profile with normal gamma for the blurays. Question is: what should I use for 3D. Is there a separate calibration method for 3D?

Also, I am using AVSForum disc for basic settings (BR and CR). How do I use it for 3D (assuming with glasses on).
I would use the same color profile but a higher (darker) gamma. I found that a 2.4 gamma with a +2 for dark level measured VERY well for 3D in high lamp. I did have to do some pretty big changes to the gains in the grayscale though. Once those were done for 100% the grayscale was REALLY good without any cut adjustments. Colors were also nearly dead on. I am getting about 17 fL through the glasses in high lamp with the iris fully open. Looks fantastic on the RS620.
 

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To get the difference, imagine a 100 watt light bulb in a 6" frosted globe. Now imaging the same bulb in a 12" frosted globe. Both would output the same lumens, and light up a room to the same brightness, but when looking at the globes, the 12" one would be 1/4 as bright as the 6" one.

Also, brightness doesn't change as you move away from a source. The size gets smaller, but the brightness stays the same.

But when you move away from a light source, the lux goes down.



To convert from ft-L to NITs, multiply by 3.426

Now going from scratch,
In ft:
16:9 105" diagonal is 91.5"x51.5" = 7.63'x 4.29', which is 32.7 sq ft.

So ft-L = 1500x1.3/32.7= 59.6, the same you got.
And in NITs, 59.6x3.426 =204.2 NITs, which is bright!

Now do the same calc in metric units:

16:9 105" diagonal is 2.66 m diagonal = 2.32m x 1.31m, which is 3.04 sq m .

So NITs = 1500x1.3/3.04/3.14159= 204.2 NIT


Note the divide by PI is in the NIT calculation and missing from the ft-L one. This is due to the definition of a ft-L, as 1/PI candela/ sq ft, whereas, a NIT is 1 candela/sq m. So the "divide by PI" is already in the definition of ft-L.

Thank you very much! I've bookmarked your reply for future reference.

It looks like I should have adequate brightness for HDR. I find 105" a nice image size for 16:9, and maybe I can go a bit bigger when watching scope movies in HDR.
 
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Just a general note on HDMI cables, related to the JVC and any other setup as well...

I know most know of you know this, but HDMI cables really are a bad design for what they do, especially given how the same cable from 10 years ago now should pass 10 times the data with all of the advancements in audio and video. In my setup, Denon 6300H, Oppo 203, JVC RS500, I'm able to run and view all of the different 4k UHD color setups without a problem - at least that is what I thought, sort of. First, my cables are 9 year old Blue Jeans cables, whatever the best ones they had at the time. When I upgraded the projector a few weeks ago from my RS1 to the RS500, I obviously needed to also change out the receiver and bluray player to get the latest HDMI spec, so the new formats of audio and video would work as they should. At the time I was worried that my 35' cable from the audio room to my projector wasn't going to work... Well it does work. However, back to my original point, they really suck and have a finicky darn interface.

Everything was working fine, seeing 4k(12bit) signal from the latest BT2020 setup, 3D, 709, it all was calibrated and looked and sounded great. Until I messed around the other day running the Ethernet line 35' to the projector so I could calibrate my RS500 with ARVs tool. Earlier today I was testing more gamma curves in 4k BT.2020 from the Oppo 203 while the RS500 kept showing 1080p during sync and the JVC menu - while I could see I was outputting 4k UHD HDR just fine. I tested many different discs, I couldn't get the projector to receive 4k and started to wonder what was going on. Well, I remembered, CHECK the HDMI cables. Everything looked fine, but I remembered pulling out the HDMI from the projector when I put in the Ethernet line. So, I carefully removed it again, then checked loose alignment as I always do to be sure that there is ZERO stress on the cable/connector when it is in the installed position - full contact, and doesn't feel like it is being pulled or twisted prior to insertion. Well after I did that, everything works perfectly again - 4k sync, all the glory is back.

So, for those who have a similar set up, long runs, lots of cables - LOTS of money spent on all this stuff, be sure that each end of your HDMI cable is seated WITHOUT stress to connector. My Blue Jeans cables are 9 years old, they work great, they are also very thick and do not bend much. So, on the back of my AV rack I have cross bars in place so that each cable can be tie-wrapped to the bar as it passes up or down heading toward the HDMI connector on my AVR. I pre-bend them each a bit, twist them accordingly so that they do not feel like they are having any place they want to be but in the spot they are going prior to insertion. If you can't, rig something up, hook the downstream to something so that the connector end makes a perfect connection.

It works. I can't tell you how many times this has happened over the years, thinking this or that is bad when these darn HDMI cables just need to be seated perfectly without stress for everything to work - and now with the high data rates associated with what we are working on, it REALLY MATTERS!

Just my $.02.

Brian
 

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I would use the same color profile but a higher (darker) gamma. I found that a 2.4 gamma with a +2 for dark level measured VERY well for 3D in high lamp. I did have to do some pretty big changes to the gains in the grayscale though. Once those were done for 100% the grayscale was REALLY good without any cut adjustments. Colors were also nearly dead on. I am getting about 17 fL through the glasses in high lamp with the iris fully open. Looks fantastic on the RS620.
Sorry for the newbie question: How do you perform Grayscale calibration in 3D? Assuming that putting 3D glasses in front of the meter is silly.
 

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Here's the main point I am confused about HDR. How is it that running on high lamp or having a high gain screen helps? :confused: I'm confused because I would think that all this would do is make EVERYTHING relatively brighter or darker.
Because HDR, despite it's name, isn't about more dynamic range, it's about higher brightness. SDR is mastered up to 100 nits, HDR supports up to 10,000 nits. In the theater, SDR is mastered up to about 50 nits (14fL), where as HDR goes up to 108 nits (IIRC).

High gain screens, high lamp mode, more open apertures, all help get us closer to supporting the higher brightnesses that HDR supports/calls for.

For example let's start with high lamp mode. The black levels increase just as much as the dark levels when moving the lamp to high mode. If that's the case, I would think the extra brightness would not help increase the HDR headroom, because all the stuff under the HDR highlights area is getting cranked up too.
This is where the curve comes into play. If you build your curve manually, then you adjust it so all the "MTO" content falls right where it's supposed to, or maybe a little low, and then you use the extra "headroom" for the highlights.

Like I said above, my SDR calibration is for about 50nits. My HDR preset supports 100-125 nits (depending on lamp mode). When I built my custom curve, I calibrated everything up to 50%/reference white "100 nits" to follow a 2x multiplier, so it should match SDR very closely (though obviously a bit higher black level), then I've got 50-75 nits on the high end for highlights.

Can someone clear up to me why the units being used here in discussing HDR is "nits?" Usually we use lumens in the projector domain, don't we?
Lumens are a measure of the light emitted from the projector, but this number is useless, because that's not what we see.

nits, like foot-Lambers and candella/square meter, are a measure of the light emitted (or in the case of projection reflected) off the screen. This is really the important metric, as this is what we see.

Bus as I understand it (which I surely don't) "nits" is the brightness of the display. But don't we care about the brightness of the image from the screen, and hence the lumens/screen combo numbers?
nits are just a different measurment of luminance, like fL. Lumens is really only useful for predicting on screen luminance before you buy hardware, once you've got your system on hand, Lumens is meaningless.

Anyway, if we have to use nits...how do I find out how many nits I will have at a certain screen size? Is there a calculation from lumen output to nits that would help me establish at what screen size I can achieve the magical 100 nits from my RS600 projector? (And how large an image I can get to?)
nits you measure off screen, that's really the only right way to do it. Though you can estimate it, if you have to, 3.4 nits is about one 1fL.

I have a question for those in the know.

We all know SDR movies are graded on a display set to max output of 100NITs.

For HDR, we hear the term reference White is 100 NIT.

I for one, am confusted by the term reference white. Does that mean diffuse white? (e.g. What a perfectly white piece of paper would reflect), or something else.

To my knowledge, there is no such term for SDR. It has been said, that SDR and HDR grades should look similar (regarding light level), other than for highlights. I take that to mean, for mid level grays, one should expect the same light level between the 2 formats.

So for example, for a 50% video SDR input, the output signal is about 20% full scale, or 20NITs when graded for 100NIT peak. So I would expect the same scene to have a 20 NIT output in HDR.

So my question is, for a 100NIT HDR input (reference white), where is that suppose to map to in SDR? Certainly it is not 100NITs. Which implies that their is a roll off in SDR that starts well before 100 NITs.
As I understand it, 100 nits HDR, which is about 50% input, is 100nits SDR, or 100% input.

On the surface, it appears we have a difference of opinion, or perhaps the wording of each reply made different assumptions, concerning the impact of High Lamp on the available Dynamic Range.

The first reply suggests that switching to High Lamp increase the available Dynamic Range, which would be of clear benefit when displaying HDR content.
No disagreement, just looking at different things. HDR is all about higher brightness capabilities for hightlights. Remember SDR goes to 100 nits, HDR goes to 10,000 nits, 100x brighter.

Opening up your iris, going to high lamp, high gain screens all increase the available brightness, which allows you to cover more of that extra brightness HDR supports, meaning more "eye-viscerating" highlights, higher color luminances, and overall more of the benefits that HDR brings.

Of course we live in a world of finite technology, and as with all things there are tradeoffs, namely elevated black level.

The second reply indicates that since the black floor is also raised in High Lamp, the effective available Dynamic Range is unchanged. The benefit comes from the use of DI (which requires the Linker), or even just a smaller aperture compared to wide open, to enhance contrast and produce a superior image with wider dynamic range.
In reality dynamic range is probably diminished, since opening the iris reduces native contrast. This is why for so many of us, getting the DI back is critical to enjoying HDR.

Or are they saying the same thing, but stating it differently??
Just looking at different sides of the the same issue.

I understand what you are saying, but not sure it explains why high nits are so important. I mean, I know they are, but still trying to understand the concept here. For instance, Manni IIRC is running high lamp with iris fully open (0) for HDR. So no contrast gain here compared to if he was using low lamp. So what are those extra nits buying him, when the entire range is increased equally in brightness in high lamp compared to low lamp?
It's covering more of the HDR highlight range, allowing for brighter and more "eye-viscerating" highlights, plus higher color luminances (as Kris likes to remind us). Which, after all, is the whole point of HDR
 

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Arve's tool

Hey folks, I find I'm having to back my contrast off too much like to minus 10 or so on the Panni to clip at 4000 nits and this makes the picture dull...any suggestions on what to change

Toggle white normal
Max bright=650
Ref white 100
Soft clip white 450
Hard clip 4000
Clip end slope 1
Soft clip method 0
Soft clip gamma 1

120" diag screen, 1.0 gain, 14 ft throw, high lamp

Thanks folks
 
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