Yea the one below looks much much more realistic and natural, but the background yellow is totally washed out…
Colour wise I would prefer the bottom one …
I came across this issue of mismatch between the source colorspace and the display colorspace last year after Win got us our HDFury devices. The Vertex2 firmware default was to indicate DCI-P3 to the Dolby Vision processor in the player and the colors output by the player were meant for a display set to DCI-P3. These defaults were there because the original guys who did the LLDV hack used JVC Projectors with a custom DTM curve in a DCI-P3 colorspace, so that’s why HDFury put those defaults into the firmware. Not knowing any better, users like me with BT2020-only projectors like my BenQ were getting this “red push” so we attempted to radically adjust our already calibrated projectors to deal with it, often with some significantly different calibrations from HDR10 that dramatically cut back on Red. I never got it quite right.
A few months later when I was on AVSForum, everyone was talking about how the “red push” had been solved for many by simply setting the Dolby Vision Data Block to BT2020 instead of DCI-P3. I did that and went back to the original HDR10 calibration of the projector before accounting for the “red push”. The colors were perfect.
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Yes Sammy, which is also why I don’t calibrate the screen to dci-p3 colour space, it’s always rec2020 or Rec709. Although the BenQ is capable of close to 100% dci-p3 colour space
One of the reason we should not calibrate to this gamut is because when you do that, it says red 235,16,16 or 940,64,64 should produce 0.68, 0.32. But if you are doing BT2020, the brightest triplet would be 209,71,16 to produce that 0.68, 0.32 chromaticity. So the problem here is that the amount of luminance wont be DCI-P3s R+G+B values that equates to D65. They are just arbitrary colours as far as calibration goes
So I stick to Rec709 with the vertex. The results are much more accurate colours compared to using rec2020 calibration to its 50% saturation targets
The settings I use on vertex2 is all set to REC709 at the moment. They look correct to my eyes
My earlier screenshot was HDR10. Tonight, I looked at the same Mulan screenshot in Dolby Vision. Dolby Vision preserved more specular highlight detail than HDR10, but it was not as good as the detail in Desray’s shot tone mapped by the Lumagen. Sorry but forgot to snap an iPhone pic.
Additionally, Our BenQ projectors don’t have a DCI-P3 color space setting. It’s BT2020 for HDR and Rec 709 for SDR. The JVC and Sony projectors have a DCI-P3/BT2020 toggle for HDR. On the JVC, I’m told that lines up nicely if you set the Vertex2 to tell the DV processor to use DCI-P3
I think our discussion on getting the “right” BT2020 is more appropriate in the other thread: Why it is so hard to calibrate HDR on a Projector and more
Let me briefly just point out the way Lumagen Radiance Pro do HDR since this thread is on Lumagen Radiance Pro. There are 2 ways to do it. One is to calibrate calibrate to SDR 2020 using SDR test patterns built in the Lumagen (advocated by the founder of Lumagen) and the other way is the software calibration creator (in my case Chromapure). Both have a different take on how HDR should be calibrated on a projector. The punchier, detailed but more “reddish” tone that many have had an opinion about is largely due to the use of expanded color modes or what mostly known as WCG. SDR in 8-bit can only reach within the Rec 709 gamut. There are far more different shades of red, green and blue (formed the primaries) and secondaries.
To date, doing 3D LUT in a colorspace is NOT perfect (as of 2019) for all home-based calibration software for projector, which is to say that none of us can firmly say that this IS or IS NOT how a HDR PQ should look like. In Lumagen camp, SDR 2020 is the way to go as it believe projector is unable to provide a good HDR image due to its low nit (hovers around 400 - 500nits) hence it is neigh impossible to do a proper 3D LUT calibration using purely HDR test patterns. Instead Lumagen utilize its own proprietary EOTF PQ curve to reproduce HDR but in SDR 2020 container. The result is more natural PQ that is nearer to SDR content (almost like Rec 709). Depending on the intrascene, SDR 2020 will shine when specular highlights are shown displayed and to capture those moments.
For Chromapure, it has a set of HDR10 gamma tone curve (HDR10-Projector, HDR2020, HDR10 with black compensation) and advocate the use of those in conjunction with their own set of HDR test patterns suited for HDR display. The software aspect is more versatile as it targets more on a general display market for both TV and projector or even a good gaming PC monitor. The results will be different depending on the content you played. This will often result in more vivid colors and warmer color tones bordering “red”.
At the end of the day, BT 2020 should push for “more shades of primaries and secondaries” whenever a HDR metadata is flagged by the source to the display. It is up to individual display (projector or TV) how well it can do their tone mapping. We are used to Rec 709 because for the longest time we have been watching bluray content authored in Rec 709 at 8-bit YCC 4:2:0. The moment we are presented with more vivid colors, we tend to question ourselves is this correct? That doesn’t look natural at all, especially the skin tones but there are times you can’t deny that the luscious green pastures or the bright burning cinder and the bright luminous stars in the dark skies look breathtaking.
And yes, both JVC and Sony projectors are capable of displaying P3 colors albeit not 100% as it is not possible for modern display to show all that shades and hues, definitely not for Low nit display like projector. The safest way to calibrate is still SDR (using Rec 709 or SDR 2020) depending on your display and the accuracy of your color probe. I will say if your display is capable of displaying “more than Rec 709 colors” then one should always calibrate at BT 2020 but make sure to set the target reference gamut in your calibration software to BT 2020 before you start calibrating. So far, I’m still experimenting with SDR 2020 and HDR 2020 calibration and the former produce more stable results compared to the latter because of the color probe limitation to do a proper 3D LUT calibration. I believe there is a probe out there that can do that but it will definitely not be cheap.
Keep your observations and comments coming. 
Desray, can you share the SDR 2020 version on the mulan when you have the time ? So we can see the specular highlights at the background comparing the HDR 2020 version?
Yes I think you are correct in some ways that we are so used to REC709 colours, sometimes when I zoom in back to the OLED , I find it really a bit saturated and when it comes to animation, those you really want the colours to shine
Animations like croods 2, trolls… lotsa content with rich colours
Having said that, after some time, personally I feel so much more comfortable looking at the rec709 type of colours, it’s also the reason I didn’t follow the advice of the pros to set it to BT2020
I revert to rec709 and after that the colours etc all look spot on with HDR
SDR2020 on the lumagen looks like worth exploring, as the pictures look so much more natural whilst preserving specular highlights
This is the dilemma that all of us are facing if we play with projector…Of course, the easiest way out is simply to calibrate to Rec 709 and then forget it…but that’s not right…how can I justify the purchase of the Lumagen and only resort to normal Rec 709 calibration which is a breeze walk in the park for any high end performance projector. We should push the limit and try every possible combinations to see which is the best route to take in our endeavor to achieving good HDR image. This is just like how you spent do much time, money and effort to achieve the best in sound department. For me, it is the same, its just that our focus is different - I’m in the video department. 
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Desray, I hear you, but I think there is just too much red for it to be realistic Here’s a comparison of black faces in sunlight between your earlier shot from Black Panther and mine. As you pointed out the greens are more luscious, but is that what the director intended?
Quite amazing though how the Lumagen brought out that leg in the background between the two women. Really powerful DTM
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That image is taken when I’m calibrated at HDR 2020 iirc. I have went through several iterations of calibrations since then. I believe that is calibrated in HDR 2020. I will need to replay again and take another pic for comparison. When it comes to Lumagen, I am barely scratching the surface as there is many other options which I have yet to explore and most of which will have an impact on HDR. I will just need more time to play with various combinations (e.g. HDR 2020, using color intensity at 65% - 75% as recommended by Chromapure creator) along the way to achieve what’s best. It will get optimized eventually. That’s the fun of it.
Oh speaking of details, that is Lumagen’s tone mapping at work here. Agreed it is one of its selling features.
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I have confirmed that the image which has a more “reddish” tone is indeed in HDR 2020 colorspace. Here’s a recap.
Here is the most recent calibration I have done using SDR 2020 colorspace as the basis to calibrate for HDR. As you can see, there is clearly a big difference. To further excite your visual palate, I present to you 2 forms of SDR images. The one on the left is SDR 2020 with HDR flag turned “on” while the one on the right is with HDR flag turned “off”.
The one on the left has a more “contrasty look” to it with a slight crush on the shadow details but otherwise has the same details. In terms of colors, you can also see there is a different shade of “green” which sports a darker shade for the one with HDR flag turned “on” compared to the one with HDR turned “off”.
Note: The SDR 2020 with the HDR flag turned “off” is what most Lumagen Radiance Pro users are using in the AVSforum.
(Image on the left - HDR flag turned “on”)
(Image on the left - HDR flag turned “off”)
I will attach my Chromapure calibration report (in pdf) for reference. It is for the Rec 709 mode to show you how good Lumagen Radiance Pro calibration is when it comes to calibrating Rec 709. A good Rec 709 will be used to further calibrate for the SDR 2020 mode.
Is this the best? I don’t know as once again, I have no basis to tell what is the standard for a BT 2020 colorspace for 4K HDR content. I will continue to explore all kinds of combinations to see which is better until I see a true 4K HDR image being displayed on a true studio calibration monitor which can display a whopping 4,000nits. But until then, the search is still on-going…
Ya, the one at the bottom is what I like and enjoy… looks very natural indeed …
Is the one at the bottom from the BenQ 2700?
Ya but the DTM looks solid , the leg sort of disappeared into the dark ! Not able to preserve the shadow details as well
Fantastic looking SDR2020! Can preserve the shadow details at the same time the colours look right and natural !
I would, without a shadow of doubt stick to SDR2020…
For me, the SDR2020 color space with HDR turned on has the correct color tone for a black person with no “red push” and is almost identical in color tone to my shot.
Desray, could we see that Mulan scene in SDR2020 with HDR turned on
No, they were in HDR10 on a Samsung TV. Here are my two earlier shots in Dolby Vision (LLDV) on the BenQ W2700. Had to wait until dark to get good contrast. I’m seeing better shadow detail in the DV presentation of the leg in the background behind the women, but no where as enhanced as the Lumagen. Any chance of seeing the same scenes on the W5700 if you have Disney+?
Yes yes, wil be firing up the system soon, do u have the timestamp ? I can zoom in to those scenes
Sorry I don’t. The Black Panther is about 25% in and the Mulan is 50-60% in. I was snapping pics on a moving pic as my pause on the Firestick Disney+ app has an overlay
Ok. I will do it tmr…
By sheer serendipity, I have managed to get DCI-P3 colors to work perfectly on my Sony Projector after some tinkling on the Chromapure s/w. The reason I’m looking forward to DCI-P3 colors is the fact that it actually has a wider color gamut compared to BT 2020 in SDR mode.
Here’s an image of Lucy at the operation table having a conversation with her mom.
I have to disable both HDR flag as well as auto gamut conversion. The HDR metadata will be derived from the source (in this case the Zidoo Z9X) which will be used by Lumagen to perform its very own Dynamic tone mapping.
