JVC RS4500 (native 4K laser projector)

[AVSCraig]

Since I started into home theater in 2002, no, it never stops ( unless you want it to ). I should have more of a report on Monday, as it's supposed to rain here all weekend, so I'll have plenty of time to take screen shots and get other people's reaction regarding the lens.

[Pultzar]

I'm curious, is the variation between projectors so significant that we need custom calibration per unit?

Does the calibration change over time with a laser based unit?

[Kris Deering]

My initial quick comparison is the tone mapping looks muted and a bit cooler - more like a Blu-ray, than the custom gamma curves. But in all fairness, I would think having someone like Chad B calibrate the Lumagen output and tone mapping would help.

If you have certain scenes from different movies that you are using for direct comparisons that show obvious differences I'd be curious to get a list of them for my own comparisons. Also realize that the decisions that Chad made when it came to where the tone map starts and how aggressive it is may be different than the settings used in the intensity mapping. The Lumagen provides for a MASSIVE amount of variance so if you prefer the look of your custom curve you could probably emulate it easily by adjusting the values in the IM setup menu (left arrow while watching a movie). You can play to your hearts desire with those.

[AVSCraig]

If you have certain scenes from different movies that you are using for direct comparisons that show obvious differences I'd be curious to get a list of them for my own comparisons. Also realize that the decisions that Chad made when it came to where the tone map starts and how aggressive it is may be different than the settings used in the intensity mapping. The Lumagen provides for a MASSIVE amount of variance so if you prefer the look of your custom curve you could probably emulate it easily by adjusting the values in the IM setup menu (left arrow while watching a movie). You can play to your hearts desire with those.

That I have no doubt about that. If / when I get my own Lumagen I'll have more time to experiment. This is just a date, to get to know it better. 

[Madfloyd]

If you have certain scenes from different movies that you are using for direct comparisons that show obvious differences I'd be curious to get a list of them for my own comparisons. Also realize that the decisions that Chad made when it came to where the tone map starts and how aggressive it is may be different than the settings used in the intensity mapping. The Lumagen provides for a MASSIVE amount of variance so if you prefer the look of your custom curve you could probably emulate it easily by adjusting the values in the IM setup menu (left arrow while watching a movie). You can play to your hearts desire with those.

I am finding that I lose contrast when converting to SDR.  Colors aren't as rich, facial information disappears (almost like I'm losing ANSI contrast) and skin tone gets paler.   There doesn't seem to be any setting that will emulate the custom curves I have or simply using the HDR gamma set to Dark Tone 7 and Picture Tone 3.

For example, if you have the newly released Pitch Perfect, in the 2nd chapter there is a girl called 'Baloney Barb' whose freckles pop with HDR but fade into subtlety when converting to SDR.  At least that's been my experience.

[AVSCraig]

I'm curious, is the variation between projectors so significant that we need custom calibration per unit?

Does the calibration change over time with a laser based unit?

" I'm curious, is the variation between projectors so significant that we need custom calibration per unit? " - yes. That's nothing new. And a calibration takes into account your screen type, size and other environmental factors.

" Does the calibration change over time with a laser based unit? " - I should hope not. I'm thinking of having a followup calibration in another year or so, and I'll tell you then.

[ozhdht]

Since I started into home theater in 2002, no, it never stops ( unless you want it to ). I should have more of a report on Monday, as it's supposed to rain here all weekend, so I'll have plenty of time to take screen shots and get other people's reaction regarding the lens.

Yes Craig, talk about over the years never stopping! I started 'living room HT' in 1994' and 'proper' dedicated HT in 2001 with a VW10HT. Life would certainly be boring if we stopped getting new 'toys'

[Kris Deering]

I am finding that I lose contrast when converting to SDR.  Colors aren't as rich, facial information disappears (almost like I'm losing ANSI contrast) and skin tone gets paler.   There doesn't seem to be any setting that will emulate the custom curves I have or simply using the HDR gamma set to Dark Tone 7 and Picture Tone 3.

For example, if you have the newly released Pitch Perfect, in the 2nd chapter there is a girl called 'Baloney Barb' whose freckles pop with HDR but fade into subtlety when converting to SDR.  At least that's been my experience.

What are your settings for the IM used on that title (and what is the title's metadata? What gamma do you have as a base?

[Madfloyd]

What are your settings for the IM used on that title (and what is the title's metadata? What gamma do you have as a base?

Kris, I'm traveling today through Tuesday so I have to go by memory.  What I had done (in terms of IM) is use the 4 memory settings to have different max light settings (100, 200, 300 & 400) with < 2000 and >= 2000 settings.  The 100 & 200 memories are based on your preferred settings when you had the RS4500.  Recently I changed my D setting to output to HDR so I can easily flip between 3 IM settings and HDR (where I then use either a custom curve or the HDR gamma). 

Keep in mind that Pitch Perfect is just an example.  I don't have access to the meta data right now but I believe the Lumagen is choosing the < 2000. I have been comparing many titles and while the Lumagen Pro is very handy for dark titles, seeing better shadow detail and for brightness 'pop', outputting in HDR does produce richer colors and gives the scene a lot more depth.  Basically it seems to keep more black in the picture which I can't seem to reproduce when outputting to SDR.

The gamma I use when converting to SDR is 2.4.

[mark_h]

Well, I'm not entirely sure because I was bowled over by the Lumagen when I first got it.  Then I added madVR and ripped all my UHDs and over time found I just wasn't impressed as much anymore.  I actually started wondering if my projector was losing contrast or something.    Then a friend came over who had never seen 4k or HDR and wanted to see some comparisons.  He wasn't impressed with 4k and neither was I.   I have 4 different memories for tone mapping and kept switching between them trying to find the setting that would show off the HDR to no avail.

After he left I went bypassed the Lumagen tone mapping (sticking with true HDR mode on the RS4500) and was blown away - just like I used to be.  So I will have to delve deeper into the settings I have but my impression is that color is just too compromised when converting to SDR.

In my experience, the Lumagen mapping can seem to "lack HDR punch" compared to a display's native HDR mode, but there's a very good reason for that...  the display typically punches out the maximum light possible for HDR with no regard for correct colour balance.  When you use the Lumagen you are getting corrected gains, ie a calibrated image and the trade off is light.  On my OLED TV for instance, I can get peak 670 cd/m2, but with the Lumagen HDR mapping my peak is around 390 cd/m2.  In native mode my OLED is pushing way too much blue; so the image looks much brighter, but the image is much cooler than it should be.  After correction I only get to 390 cd/m2.

But I prefer accuracy... so the answer is to find a brighter display, if necessary.

One of the things the Lumagen is promising to do is a dynamic HDR10 mode, where the Lumagen itself will scan a frame ahead and dynamically adjust the HDR10 metadata to give the equivalent of HDR10+.  I imagine this will also work with HLG, which is also now supported.  And of course all of this is mapped to a calibrated 3D LUT/1D LUT for the best possible colour reproduction.

[stridsvognen]

Hows SDR looking if you calibrate a 2.5-2.6 gamma  on the RS4500.?

[AVSCraig]

We watched Passengers tonight with the Panamorph Paladin DCR lens - about 44 foot lamberts on my screen - incredible detail I don't recall seeing before. Best A lens hands down I've ever had by a large margin ! My three guests ( regulars who came over this afternoon for the lens / no lens demo ) said keep the lens! It's like a giant flat panel at times now ! The added brightness and pixels brings out details in objects in movies you couldn't see before. Screen shots coming .

I'm at 701 hours now. 

[Dylan Seeger]

Hows SDR looking if you calibrate a 2.5-2.6 gamma  on the RS4500.?

That's an awfully high gamma for SDR. No matter the projector you're going to lose shadow detail.

[stridsvognen]

That's an awfully high gamma for SDR. No matter the projector you're going to lose shadow detail.

That will depend on the max light output you calibrate to, you will flatten the curve out of black by the high gamma, but you will then ramp it up by elevating the peak light output, so ull get a more dynamic SDR image, but it calls for a good low level performance/ native on off contrast, if thats not surficiant it sure will look bad. But got the impression it should be capable of a decent light output.

So i can try ask differently.. What SDR gamma are you guys running.'?

[AVSCraig]

That will depend on the max light output you calibrate to, you will flatten the curve out of black by the high gamma, but you will then ramp it up by elevating the peak light output, so ull get a more dynamic SDR image, but it calls for a good low level performance/ native on off contrast, if thats not surficiant it sure will look bad. But got the impression it should be capable of a decent light output.

So i can try ask differently.. What SDR gamma are you guys running.'?

2.4