[[email protected]]

Maybe the JVC DTM output is not SDR, but some DTM is.

madVR DTM output is certainly SDR with a linear gamma of 2.2.

That's what HDR is all about, gamma.

Wide color gamut or bit depth has nothing to do with HDR or SDR. You can certainly have an SDR video with BT2020 color and 12-bit depth, but if it's graded to a linear 2.2 gamma, it's not high dynamic range in any sense of the term.

Just because the result of JVC DTM looks more "HDR", doesn't mean it's an HDR format or picture.

What if you captured the signal coming from the JVC DTM, and played it back on a Sony display?

For example you can do this with HTPC madVR. You could 100% record the madVR DTM output and store it in an SDR-only video container, and play it back through a display chain and on a display that only supports SDR. It is SDR, but that doesn't mean it can't look better than the studio's SDR conversation for instance. But that doesn't mean its HDR.

We're getting into the semantics of what "SDR" means. In this context it does not equate to 1080p Blu-ray which is what many think "SDR" is. What I'm saying is that tonemapped HDR is not the same as what you get from 1080p blu-ray. That's why I said madVR and Lumagen output tonemapped HDR content in an SDR "container". This is done so that the display uses gamma (2.2 or 2.4 or whatever you tell it your display is calibrate to) to match how the tonemapper is rendering the content. But what you get can still be HDR despite using a gamma based display solution. Both tonemappers give you the option to tonemap to HDR10's PQ/EOTF standard if that's what you want to use as the container instead. The only point is that SDR in this context does not equate to what you get from older SDR content found on 1080p Blu-ray.

The Lumagen Radiance Pro uses very similar terminology to describe how their tonemapper works:

A key concept to understand for HDR sources and HDR Tone Mapping is that data manipulation in the pipeline does not always have to be in “HDR Gamma.” Just as DCI/P3 movies are put into a “Rec 2020 container” for HDR, it is possible to put the HDR Gamma into a “SDR container” if this is accounted for so that the onscreen image is correct. This is not somehow converting HDR to SDR. Instead it is putting the “HDR in an SDR container.

 

[Mike Garrett]

I would add an extra requirement to that wager if I were you.
The location of the shootout should be completely dark, batcave etc.
I have seen a comparison in a not fully dark living room with white ceiling and walls and this is killing.
Still this is for many buyers a reality, they have a living room ht and have to live with all its compromises not to speak about WAF's.
I got the impression many of you are not realizing the low percentage of projector owners that have a full batcave let alone spent time on these forums

True, I assumed it would be held in a good light controlled room.

 

[cdnscg]

With bright scenes, I agree with you, but not in the dark scenes. I wish Covid was not going on, because if it wasn't, I would propose the following:

For RS2000 vs VW715 or RS3000 vs VW915. You let me pick the content and without even showing them side by side, I will go $1,000 per scene with you. You show one projector then show the other projector and I then tell you which is the JVC and which is the Sony. Every scene I get wrong is $1,000 to you. Every scene I get right is $1,000 to me. Do want the projectors set up properly, so would want them calibrated.

I am not a gambler by nature, but then this is not gambling, since I have already seen this comparison using RS1000 and VW695. In the dark scenes the difference was so large that everyone in the room laughed. In the night time scene with stars, the gray back ground of the night with the Sony, made the JVC look black, it was that much difference and the stars on the JVC were also brighter. It did not require a quick A/B to tell the difference. We will do a minimum of 12 scenes. I would source the JVC and you source the Sony.

Once covid is over, you interested?

What about them same scenario but including bright scenes? Would be curious to note the winners.

 

[Mike Garrett]

What about them same scenario but including bright scenes? Would be curious to note the winners.

That I am not willing to bet on a difference in bright scenes, because I can't tell a difference. I doubt anyone else can either.

 

[SirMaster]

Usually the content sent is unchanged, just mapped to an SDR gamma.

It doesn't work that way.

You can't have for example a 1000+ nit highlight in the same frame as darkness with linear SDR gamma. That's the whole reason HDR gammas were invented. To be able to represent things in scenes that are not possible in SDR. Hence high dynamic range.

SDR gamma is not capable of storing / representing truly high dynamic range scenes. For example, a highlight that's 1000, or even more times brighter than another element in the scene.

There is a maximum difference in nits between 2 pixels within the same frame in SDR gamma that is a much lower dynamic range than you can define with HDR gamma.

 

[Mike Garrett]

It doesn't work that way.

You can't have for example a 1000+ nit highlight in the same frame as darkness with linear SDR gamma. That's the whole reason HDR gammas were invented. To be able to represent things in scenes that are not possible in SDR. Hence high dynamic range.

SDR gamma is not capable of storing / representing truly high dynamic range scenes.

There is a maximum difference in nits between 2 pixels within the same frame in SDR gamma that is a much lower dynamic range than you can define with HDR gamma.

I got caught once again of starting a post and then forgetting to erase it, before quoting another poster. I hate this new format.

 

[HoustonHoyaFan]

Maybe the JVC DTM output is not SDR, but some DTM is.

madVR DTM output is certainly SDR with a linear gamma of 2.2.

That's what HDR is all about, gamma.

Wide color gamut or bit depth has nothing to do with HDR or SDR. You can certainly have an SDR video with BT2020 color and 12-bit depth, but if it's graded to a linear 2.2 gamma, it's not high dynamic range in any sense of the term.

Just because the result of JVC DTM looks more "HDR", doesn't mean it's an HDR format or picture.

What if you captured the signal coming from the JVC DTM, and played it back on a Sony display?

For example you can do this with HTPC madVR. You could 100% record the madVR DTM output and store it in an SDR-only video container, and play it back through a display chain and on a display that only supports SDR. It is SDR, but that doesn't mean it can't look better than the studio's SDR conversation for instance. But that doesn't mean its HDR.

Great points which is why we need to be precise with our terms.

 

[[email protected]]

It doesn't work that way.

You can't have for example a 1000+ nit highlight in the same frame as darkness with linear SDR gamma. That's the whole reason HDR gammas were invented. To be able to represent things in scenes that are not possible in SDR. Hence high dynamic range.

SDR gamma is not capable of storing / representing truly high dynamic range scenes. For example, a highlight that's 1000, or even more times brighter than another element in the scene.

There is a maximum difference in nits between 2 pixels within the same frame in SDR gamma that is a much lower dynamic range than you can define with HDR gamma.

I don't know if you've been following this thread for the entire length of this discussion, but this all started when someone posted and claimed that DTM is about converting HDR10 into the SDR standard that 1080p blu-ray uses, ie 100 nits, REC709 and 8 bit. Obviously this is not true, but the conversation has morphed quite a bit since then, so some things may be out of context here if you haven't been following.

With that said, I don't think anyone is trying to say that tonemapped HDR in a gamma based container has all the same benefits of unadulterated PQ/EOTF. All that is being said is that outputting in an SDR/gamma based container does not automatically mean HDR is gone from the image. There is a valid point to be made about a 100 nit level image brightness and what you can get out of the HDR10 source, but this is besides the point being made. There are a whole host of reasons why DTM is useful even if you lose the high dynamic range aspect of the original image. If you have more brightness to work with, you can still easily get HDR after it has been tonemapped, even if it's being output in an SDR/gamma container. I mean, HLG is gamma based and I don't see anyone here claiming that it isn't HDR.

 

[HoustonHoyaFan]

What about them same scenario but including bright scenes? Would be curious to note the winners.

Pre picking scenes is not very useful which is why serious comparisons are always double blind, preferably with a reference monitor to establish the reference image. I have seen a dozen of those comparisons.

In a personal comparison of my VW1100es to my RS600 iris closed so ~100,000:1 native:

I could likely find 12 dark scenes in Harry Potter DH2 where I could instantaneously spot differences in favor of the RS600. I could likely find 12 bright scenes in Life of Pi where I could spot differences in favor of the VW1100es.

 

[Bytehoven]

It doesn't work that way.

You can't have for example a 1000+ nit highlight in the same frame as darkness with linear SDR gamma. That's the whole reason HDR gammas were invented. To be able to represent things in scenes that are not possible in SDR. Hence high dynamic range.

SDR gamma is not capable of storing / representing truly high dynamic range scenes. For example, a highlight that's 1000, or even more times brighter than another element in the scene.

There is a maximum difference in nits between 2 pixels within the same frame in SDR gamma that is a much lower dynamic range than you can define with HDR gamma.

Best that can be done is trying to maintain some degree of gamma curve proportions within the available luminance range, in an attempt to preserve any sense of realism. But even under the best DTM it falls down compared to reproduction on high dynamic range displays.

Even when we were limited to SDR content, gamma magic was still exploited to enhance the perception of increased contrast range and the visual experience, with all the associated artifacts.

 

[cdnscg]

Pre picking scenes is not very useful which is why serious comparisons are always double blind, preferably with a reference monitor to establish the reference image. I have seen a dozen of those comparisons.

In a personal comparison of my VW1100es to my RS600 iris closed so ~100,000:1 native:

I could likely find 12 dark scenes in Harry Potter DH2 where I could instantaneously spot differences in favor of the RS600. I could likely find 12 bright scenes in Life of Pi where I could spot differences in favor of the VW1100es.

Pick your poison or preference

 

[Mike Garrett]

Pre picking scenes is not very useful which is why serious comparisons are always double blind, preferably with a reference monitor to establish the reference image. I have seen a dozen of those comparisons.

In a personal comparison of my VW1100es to my RS600 iris closed so ~100,000:1 native:

I could likely find 12 dark scenes in Harry Potter DH2 where I could instantaneously spot differences in favor of the RS600. I could likely find 12 bright scenes in Life of Pi where I could spot differences in favor of the VW1100es.

You were the one that said people could not tell the difference. Only way that happens is if you limit the content. I just said if I limit the content, I can pick it out 100% of the time. If it truly was as close as you say, it should not matter.

Try that comparison with a current Sony, because Sony has not produced a projector with contrast as good as the 1100, since 2013.

 

[cdnscg]

I am disappointed to read in the PassionHomeCinema review of the Sony 590 that he found the operating noise to be an issue. Do the Sony 590(715) and JVC NX7 need to be on high lamp to achieve good HDR, and which unit is loader in both low and high lamp modes?

 

[Mike Garrett]

I am disappointed to read in the PassionHomeCinema review of the Sony 590 that he found the operating noise to be an issue. Do the Sony 590(715) and JVC NX7 need to be on high lamp to achieve good HDR, and which unit is loader in both low and high lamp modes?

Depends on screen size, screen gain, aspect ratio and throw. But good chance high is what you would need to use.

 

[cdnscg]

Depends on screen size, screen gain, aspect ratio and throw. But good chance high is what you would need to use.

135" 16:9 ST130 G4 14' away from screen

 

[jeahrens]

I suspect that you have figured out that the out of balance DTM focus is sales shill stuff.

That's a level of flat out wrong I haven't seen in a while. Well done.

 

[Mike Garrett]

135" 16:9 ST130 G4 14' away from screen

The Sony 715, 915 nor the RS2000 can throw a 135" 16:9 image from 14'. The RS3000 is able to fill that screen size from 14'. With the 3000 you would have around 30FL in low, without the DCI filter. So yes, 3000 would work well in low lamp for HDR.

 

[Drexler]

It doesn't work that way.

You can't have for example a 1000+ nit highlight in the same frame as darkness with linear SDR gamma. That's the whole reason HDR gammas were invented. To be able to represent things in scenes that are not possible in SDR. Hence high dynamic range.

SDR gamma is not capable of storing / representing truly high dynamic range scenes. For example, a highlight that's 1000, or even more times brighter than another element in the scene.

There is a maximum difference in nits between 2 pixels within the same frame in SDR gamma that is a much lower dynamic range than you can define with HDR gamma.

I dont understand this. You always have the possibility of an infinite dynamic range in the signal. Black is coded as zero, so any value divided by 0 is infinite. What about an ansi checkerbord pattern? It will look identical no matter if you code it as HDR or SDR.

 

[cdnscg]

The Sony 715, 915 nor the RS2000 can throw a 135" 16:9 image from 14'. The RS3000 is able to fill that screen size from 14'. With the 3000 you would have around 30FL in low, without the DCI filter. So yes, 3000 would work well in low lamp for HDR.

The throw distance is actually 14.5' and works fine with my present Sony 300ES

 

[HoustonHoyaFan]

Pick your poison or preference

Don't forget your environment, your current equipment level, and your goals.

I suspect that if you ask in the VW885es thread owners who upgraded from your projector you will get one set of answers. In the JVC NX7 thread a different set. You have a very good projector and need to evaluate all choices for yourself to see which one works best for your eyes in your environment.

The one thing I can confidently say is that UHD (HDR) on any of the projectors you are considering will not approach the HDR on the flat panel you just bought so set a different expectation.