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Official BenQ LK990 Owners Thread

Official BenQ LK990 Owners Thread
« on: June 12, 2020, 03:25:21 PM »
First Impressions now using Dolby Vision LLDV:

If you see the LK990 set to HDR Brightness of -2, color at ~7 and Color Enhancement at ~16, paired with an HDFury Vertex2 doing the LLDV/Dolby Vision tweak with a DV String set to Max Luminance (nits) of 10,000 nits, or anywhere between 2,000 - 10,000 really, then you certainly will be saying "Wow"!

I can indeed get an absolutely incredible HDR/Dolby Vision image on screen with this combo.

If anyone says brightness doesn't matter, then you render the great flat panels that can do that utterly moot.  As anyone who actually knows what HDR is and does, the main and almost entirety of the movie is still within the 100 nit max range, or at least is supposed to be mastered that way, the same as its SDR counterpart.  The extra brightness is reserved for specular highlights, etc.  So by using a lower nit projector you're just forcing the display, source or tone mapping device/processor to compress that range available further down to whatever it has for its peak nits.  No compression is always better than any compression.  Tone Mapping is compression, but I am sure you already know that, so I guess that's for the newbies too.



With this higher brightness LK990, I still have the same original 100 nits brightness for the main part of the HDR video, but also the extra brightness over the lower nit projector is now there for what is easily seen as amazing specular highlights and incredible "HDR Effects", like you see on some of the best HDR/DV flat panels, which haven't been compressed by tone mapping as much or at all.



The laser levels in this projector are able to be lowered based on what is input, using the unit's Automatic Power Control and SmartEco features, similar to what is reported with the much more expensive JVC RS4500, and why many prefer its black levels and shadow details over the reportedly better RS3000 (@markmon for example).  When you input and present a 10,000 nit Dolby Vision custom string using the HDFury Vertex2/DIVA/Maestro with a BT2020 color gamut along with setting the LK990 to an HDR Brightness setting of -2, color at around 7, Brilliant Color ON and Color Enhancement to about 16.  This combo makes this happen along with great color tracking along the color gamut sweeps, unlike when you use default color at 50 and Color Enhancement OFF and Brilliant Color ON.



Couple that with all the things that make the image much more detailed than even the mighty RS4500, as easily seen in the image attached, by @Woofer.



And no, I am not going to go around and around with anyone again here.  I have it here and have for a LONG time, doing extensive testing and configurations with many different sources and signals.  Nobody else has.  I know what it can and can't do, Nobody else does.  And yes, I do agree the one area it can't compete totally is native on/off contrast and a little color saturation, and I have always said that.  But I have also always said all the other attributes this presents are far superior, and I still completely stand by that.  I can all but guarantee anyone else who sees what I see here with Dolby Vision would feel the exact same way too.


The complete stubbornness to not want to really dig deep and understand this projector and what it can do never ceases to amaze me.  I don't understand why.  Who does it hurt? You all just keep living with old thoughts and paradigms that simply don't apply here.

Please all be safe and healthy in these trying times!

https://discuss.avscience.com/index.php?action=dlattach;topic=1924.0;attach=4867
« Last Edit: June 12, 2020, 03:27:19 PM by HarperVision »

Re: Official BenQ LK990 Owners Thread
« Reply #1 on: June 12, 2020, 04:02:10 PM »
There were also some issues noted regarding the 24p motion and some color shifting (yellowing) with this projector.  I am pleased to report that it has received firmware updates to alleviate these issues, per BenQ:

Below is a recap of firmware update since 1.0:

              FW Type/Ver.                    Date Posted                      Fixes
              MStar v1.01                      04/30/2019                        Improve shuttering issue when input timing is 24Hz or 50 Hz.
              TI v1.07                              04/30/2019                        Improve shuttering issue when input timing is 24Hz or 50 Hz.
              LAN v0.05                          04/30/2019                        Each digit of IP address can be adjusted independently in Network Setting function.
              MStar v1.02                      12/11/2019                        Another source device might affect/revise the color index of the projector and could cause the screen to become yellowish.





AVSMike

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Re: Official BenQ LK990 Owners Thread
« Reply #2 on: June 13, 2020, 08:11:14 AM »
First Impressions now using Dolby Vision LLDV:

If you see the LK990 set to HDR Brightness of -2, color at ~7 and Color Enhancement at ~16, paired with an HDFury Vertex2 doing the LLDV/Dolby Vision tweak with a DV String set to Max Luminance (nits) of 10,000 nits, or anywhere between 2,000 - 10,000 really, then you certainly will be saying "Wow"!

I can indeed get an absolutely incredible HDR/Dolby Vision image on screen with this combo.

If anyone says brightness doesn't matter, then you render the great flat panels that can do that utterly moot.  As anyone who actually knows what HDR is and does, the main and almost entirety of the movie is still within the 100 nit max range, or at least is supposed to be mastered that way, the same as its SDR counterpart.  The extra brightness is reserved for specular highlights, etc.  So by using a lower nit projector you're just forcing the display, source or tone mapping device/processor to compress that range available further down to whatever it has for its peak nits.  No compression is always better than any compression.  Tone Mapping is compression, but I am sure you already know that, so I guess that's for the newbies too.



With this higher brightness LK990, I still have the same original 100 nits brightness for the main part of the HDR video, but also the extra brightness over the lower nit projector is now there for what is easily seen as amazing specular highlights and incredible "HDR Effects", like you see on some of the best HDR/DV flat panels, which haven't been compressed by tone mapping as much or at all.



The laser levels in this projector are able to be lowered based on what is input, using the unit's Automatic Power Control and SmartEco features, similar to what is reported with the much more expensive JVC RS4500, and why many prefer its black levels and shadow details over the reportedly better RS3000 (@markmon for example).  When you input and present a 10,000 nit Dolby Vision custom string using the HDFury Vertex2/DIVA/Maestro with a BT2020 color gamut along with setting the LK990 to an HDR Brightness setting of -2, color at around 7, Brilliant Color ON and Color Enhancement to about 16.  This combo makes this happen along with great color tracking along the color gamut sweeps, unlike when you use default color at 50 and Color Enhancement OFF and Brilliant Color ON.



Couple that with all the things that make the image much more detailed than even the mighty RS4500, as easily seen in the image attached, by @Woofer.



And no, I am not going to go around and around with anyone again here.  I have it here and have for a LONG time, doing extensive testing and configurations with many different sources and signals.  Nobody else has.  I know what it can and can't do, Nobody else does.  And yes, I do agree the one area it can't compete totally is native on/off contrast and a little color saturation, and I have always said that.  But I have also always said all the other attributes this presents are far superior, and I still completely stand by that.  I can all but guarantee anyone else who sees what I see here with Dolby Vision would feel the exact same way too.


The complete stubbornness to not want to really dig deep and understand this projector and what it can do never ceases to amaze me.  I don't understand why.  Who does it hurt? You all just keep living with old thoughts and paradigms that simply don't apply here.

Please all be safe and healthy in these trying times!

https://discuss.avscience.com/index.php?action=dlattach;topic=1924.0;attach=4867
Dave, you keep trying to make HDR all about brightness. When the very name is High Dynamic Range. That is not referring to brightness. If brightness is the end all be all for HDR, then the LCD flat panels would easily provide the best HDR image and yet it is clearly undisputed that an OLED TV provides a much better HDR image and the OLED TV's have less than half the brightness of some of the LCD TV's. What is it that an OLED has over an LCD flat panel, it is contrast.
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Mike Garrett
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JVC, Sony, Epson, Marantz, Denon, Yamaha, Stewart, Seymour, Screen Innovations, Screen Excellence, DNP, Da-Lite, Triad, SVS, Martin Logan & more.

Re: Official BenQ LK990 Owners Thread
« Reply #3 on: June 13, 2020, 02:42:42 PM »
Dave, you keep trying to make HDR all about brightness. When the very name is High Dynamic Range. That is not referring to brightness. If brightness is the end all be all for HDR, then the LCD flat panels would easily provide the best HDR image and yet it is clearly undisputed that an OLED TV provides a much better HDR image and the OLED TV's have less than half the brightness of some of the LCD TV's. What is it that an OLED has over an LCD flat panel, it is contrast.
I'm sorry, but that's not what I am doing at all.  Although you guys seem to be making it all about black levels and contrast. It also wasn't about being a contest, although you guys also made it about that too.

Re: Official BenQ LK990 Owners Thread
« Reply #4 on: July 03, 2020, 09:41:58 AM »
Thanks for the info Dave. I think that all the owners of this unit that are not using DTM should definitely see a huge benefit from this mod. I have had an LK series unit for over 2 years and I still enjoy the unit greatly. I think that the room, content and personal preference all factor in when evaluating this unit or any other display. Prior to DTM, the LK's brightness was a huge advantage in dealing with a static map. With the introduction of DTM, the frame by frame mapping has evened the playing field a bit for projection units of standard brightness. Yes, the black floor of these units measure poorly, but the room environment and content will reveal how much of a problem that actual is IRL. I am using my unit probably 40% movies, 30% gaming and 30% sports.

Re: Official BenQ LK990 Owners Thread
« Reply #5 on: July 07, 2020, 09:41:57 AM »
Thanks for the info Dave. I think that all the owners of this unit that are not using DTM should definitely see a huge benefit from this mod. I have had an LK series unit for over 2 years and I still enjoy the unit greatly. I think that the room, content and personal preference all factor in when evaluating this unit or any other display. Prior to DTM, the LK's brightness was a huge advantage in dealing with a static map. With the introduction of DTM, the frame by frame mapping has evened the playing field a bit for projection units of standard brightness. Yes, the black floor of these units measure poorly, but the room environment and content will reveal how much of a problem that actual is IRL. I am using my unit probably 40% movies, 30% gaming and 30% sports.
Please DO NOT lump all "LKs" together!  The LK970 and LK990 are two completely different beasts, just as the Epson LS10000 and LS10500 are.  One accepts and displays HDR and the older one doesn't.  I tried applying some of my older HarperVision techniques from the LK970 on the LK990 and it in NO WAY worked the same.  This implies that the FW and SW and most likely main boards are totally different.

The inclusion of SmartEco laser dimming on the LK990, added to the existing Automatic Power Control dimming carried over from the LK970, now combined with Dolby Vision/LLDV DTM makes the resultant image far above any that I ever saw on the LK970, which was extremely good for its time with static maps, as you say.  If you like the LK970, you'll absolutley love the LK990 with these additions.

I also have my LK990 here with me in PA while I am visiting.  I decided to send it in to BenQ to get the FW updated to 1.02 (see above post for what is fixed) while I was away, then decided just to have them send it to me here on PA when it was done.  I also decided to try it on a different screen here, the Elite Screens Aeon Cinegrey 3D and I have to say it is a nice improvement in contrast, making this even better when combined with all the other attributes which make this projector ahead of others in its class, in my humble opinion of course.  

I noticed that the FW update fix for the yellowing issue, I think, is giving much better colors now.  The reds and greens seem so much more saturated, especially red.  It is easily seen by the naked eye.  I don't have my meters here with me, but it is pretty obvious.  I can't wait to measure the new gamut, but It could of course be due to the different screen.  I won't know until I can measure.

If anyone is around the northeast USA, I would be willing to maybe bring the LK990, Sony X800M2, TiVo Stream 4K over for a demo, but I really also need an HDFury Vertex1 or 2 so we can also do an LLDV Dolby Vision demo.  Or someone could come here to see it on the new screen.  Shoot me a PM here and we can try to coordinate, but I do have a lot scheduled while I am here already with family, friends, etc. plus I mangled my leg in a nasty fall while hiking and the next day my 4 year old granddaughter decided to slide down her steps in a laundry basket, pretending it was a pirate ship on the high, wavy seas, therefore totally snapping both bones in her forearm between her wrist and elbow!  It was quite a sight as her arm was as wavy as the ocean! :eek:  We both spent the day in the ER getting x-rays. :-(

AVSMike

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Re: Official BenQ LK990 Owners Thread
« Reply #6 on: July 07, 2020, 11:45:27 AM »
Sorry to hear about your granddaughter. We had both our son and daughter with broken arms at the same time. I was not the one looking after either of them during their incidents. :) 
My Baffle Wall System: https://discuss.avscience.com/index.php?topic=124.msg902#msg902

Mike Garrett
AV Science Sales
585-671-2968
mike@avscience.com

JVC, Sony, Epson, Marantz, Denon, Yamaha, Stewart, Seymour, Screen Innovations, Screen Excellence, DNP, Da-Lite, Triad, SVS, Martin Logan & more.

Re: Official BenQ LK990 Owners Thread
« Reply #7 on: July 07, 2020, 09:33:08 PM »
Sorry to hear about your granddaughter. We had both our son and daughter with broken arms at the same time. I was not the one looking after either of them during their incidents. :)
Thanks Mike! :-)

I am happy to report that I wasn’t the one watching my granddaughter either. Mom was home and even upstairs with her when she pirated her way down the seven seas.....I mean steps! ;D

Re: Official BenQ LK990 Owners Thread
« Reply #8 on: July 17, 2020, 11:56:35 AM »
Quote from: AVSMike
Why is this answer ridiculous? back years ago, before Shifting DLP, when on off contrast for DLP was higher, the recommendation for anyone that was serious about image quality, they were advised to turn off DB. Javs was seriously interested in the LK990, because it was one of the few projectors that might have had enough light output to light up the size screen he was wanting and in his budget. Javs is pretty serious about image quality and could not live with the artifacts DB introduced, so he reviewed the projector without DB on. Each person has to decide if the benefits of BD outweighs the cost. ........

Mike posted this elsewhere, but it needs to be cleared up. The BenQ LK990 doesn’t have or offer DB (Dynamic Black) setting. It uses SmartEco and Automatic Power Control for laser dimming to increase contrast ratios. I just looked in the service menu last night and there is a setting in there for DB, but it is turned off/disabled.

I believe what Mike is referring to with Javs was BC (Brilliant Color), which he turned off for his calibrations, which I don’t agree with. Especially now because the problem is fixed and alleviated with firmware version 1.01 and 1.02. These have greatly enhanced the color performance of the LK990.

AVSMike

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Re: Official BenQ LK990 Owners Thread
« Reply #9 on: July 18, 2020, 09:06:47 AM »
I have added a note, correcting my statement about Jav's turning off BC, rather than DB.
« Last Edit: July 18, 2020, 09:10:13 AM by AVSMike »
My Baffle Wall System: https://discuss.avscience.com/index.php?topic=124.msg902#msg902

Mike Garrett
AV Science Sales
585-671-2968
mike@avscience.com

JVC, Sony, Epson, Marantz, Denon, Yamaha, Stewart, Seymour, Screen Innovations, Screen Excellence, DNP, Da-Lite, Triad, SVS, Martin Logan & more.

Re: Official BenQ LK990 Owners Thread
« Reply #10 on: July 18, 2020, 11:40:08 AM »
I have added a note, correcting my statement about Jav's turning off BC, rather than DB.

Thanks Mike. As you, I like to make sure accurate things are posted for any future readers and owners.

In this regard, this is also incorrect, unless of course you don’t bother calibrating and setting it up so it is accurate:

Quote
Added 7/18/2020

It was pointed out to me that it was Brilliant Color in the LK990 that Javs turned off, not dynamic black. The 990 does not have dynamic black in the regular menu. Brilliant Color is another bit of processing that should be turned off, if you want an accurate picture.

I have found if you greatly reduce the main color control to less than 10 (I use about 7) and then go the Advanced Menu->CineMaster->Color Enhancer and set it to about 14-18 (I use 16) then the color tracks very nicely with Brilliant Color ON.

This is of course on the LK990, but I am sure you can get similar results on other projectors with BC and color enhancement options, like the UHZ65. 

Javs

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Re: Official BenQ LK990 Owners Thread
« Reply #11 on: July 18, 2020, 06:56:22 PM »
I have found if you greatly reduce the main color control to less than 10 (I use about 7) and then go the Advanced Menu->CineMaster->Color Enhancer and set it to about 14-18 (I use 16) then the color tracks very nicely with Brilliant Color ON.

Since the only way you can possibly know that is by measuring it, hence you have the calibration file on your PC, can you please share the colour volume tracking results for any primary colour, say, green?

If you are correct, your deltaE for Y should be reasonable.

For reference, here is BC Off. This is Rec709 mind you... Note the two red circles, Y Target and Y measured. They are close enough to consider reasonable that there is no issue.

https://i.imgur.com/6KB1f8z.png
Official BenQ LK990 Owners Thread


Not like this:

BC ON, which from a standpoint of how the technology works based on what I read about it and even what you yourself have agreed, its my understanding its NOT possible to have the green with BC On reach the target Y which as you know is a target in relation to the measured white.

If you have found a way around that, then that's great! But you should be easily able to show us so we can see the measurements.

https://i.imgur.com/D758nBK.png
Official BenQ LK990 Owners Thread


Also, note how much better tracking is overall with BC off, but also note that to the untrained (Not saying you at all)
the tracking on BOTH appears to be somewhat reasonable (excluding Magenta) if one was looking only at the CIE chart, however the colour volume in comparison to the measured peak white takes a shit when BC is on. Hence, unusable to me.
JVC X9500 (RS620) | Marantz AV7702 MkII | Emotiva XPA-7 | Emotiva 5175 | Rotel RMB-1555B | iNuke 3000DSP | Javelin Audio 7.4.2 System

Re: Official BenQ LK990 Owners Thread
« Reply #12 on: August 27, 2020, 12:10:10 AM »
Since the only way you can possibly know that is by measuring it, hence you have the calibration file on your PC, can you please share the colour volume tracking results for any primary colour, say, green?

If you are correct, your deltaE for Y should be reasonable.

For reference, here is BC Off. This is Rec709 mind you... Note the two red circles, Y Target and Y measured. They are close enough to consider reasonable that there is no issue.

https://i.imgur.com/6KB1f8z.png
Official BenQ LK990 Owners Thread


Not like this:

BC ON, which from a standpoint of how the technology works based on what I read about it and even what you yourself have agreed, its my understanding its NOT possible to have the green with BC On reach the target Y which as you know is a target in relation to the measured white.

If you have found a way around that, then that's great! But you should be easily able to show us so we can see the measurements.

https://i.imgur.com/D758nBK.png
Official BenQ LK990 Owners Thread


Also, note how much better tracking is overall with BC off, but also note that to the untrained (Not saying you at all)
the tracking on BOTH appears to be somewhat reasonable (excluding Magenta) if one was looking only at the CIE chart, however the colour volume in comparison to the measured peak white takes a shit when BC is on. Hence, unusable to me.

Sorry for the late reply.  I have been away for a couple months.  No I don't have those sweeps yet.  I only did quick measurements using UHD discs since as I said, I don't have a pattern generator at the moment.  I did not do a saved workflow as at the time it was only for testing of the theory.  I stumbled onto this tracking fix and then dismounted my LK990 to send to BenQ for FW updates while I was away.  I still have not received it back here since I shipped it back from PA.  I  couldn't do any calibrations there because I didn't have any of my gear whatsoever.  I was even compelled to buy another Sony X700 and HDFury Linker so I could demonstrate LLDV on the LK990 to Aztar.  He can comment on colors, etc., but there were many issues uncorrected when I went there, due to not being able to calibrate or use a custom LLDV profile on the Linker like you can on the Vertex2.  I should have my LK990 on Sep 2 according to FedEx.

To answer your color volume (mis)information, I have explained this previously on many occasions, both here and on AVSF before everyone's concerted efforts to have me banned there due to the their ignorance of facts such as this and many more.

Here is but one instance not long ago in May, before said ignorance leading to that thread to be closed too:

https://discuss.avscience.com/index.php?topic=1924.msg16898#msg16898

Quote from: HarperVision
......WRGB OLEDs come to mind due to their white pixels being mixed in with the RGB, where you have to lower Y luminance so much to get full 3D color luminance measured properly.  Javs saw this and complained that he had to turn off Brilliant Color, which I disagree with when done properly in the end.  These projectors were engineered from the ground up, taking this into account, as the Delta/Vivitek and Optoma engineers told me.  This is the same with the WRGB OLEDs.  The LK990 with it's RGBY (Y being derived from the phosphor wheel, excited by the blue lasers) imparts similar issues, as you, me, Kris and Javs have all noted when measuring the LKs.

The issue on projectors which impart RGBY laser phosphor/color wheels aren't as widely known, but it is certainly in the same vein as WRGB OLEDs, and as such you have to compensate for this with some special offset settings when calibrating, as you can see here in the dropdown in CalMAN when setting it up, preparing for your calibration session, just as if you were calibrating one of the OLED (White) displays which react in a similar manner:

https://i.imgur.com/xXEZecW.png
Official BenQ LK990 Owners Thread


So it was you, not me who is and was wrong, because you apparently never selected the proper "Meter Mode (Target Display Mode)".  In the case of the LK970/990 projectors, you need to select the one I circled in yellow in the image above, the setting for the "Projector (Laser Phosphor) - Panasonic RZ970" because that model also uses RGBY phosphor/color wheel.

To this end, what they also do is use Brilliant Color to expand the color saturation to compensate for the lack of color luminance (which I also mentioned many times previously), which is realized due to the Helmholtz-Kohlrausch (HK) effect, whereby increasing the perceived color brightness/luminance by increasing color saturation, i.e. - what Brilliant Color is also used for.

As I have said, this is exactly what a Delta Engineer who developed their high brightness RGBY Laser Phosphor HDR DLPs explained to me when I asked him this exact question, and reported here and on AVSF, to deaf ears apparently.

And surprise, surprise, you posted this over on AVSF.  "Color Harmonizer" is just a fancy name for "Brilliant Color".  I used to sell these Panasonic RZs for Audio General:



This portion of an image you shared there basically shows RGBY Laser Phosphor with their version of Brilliant Color, Color Harmonizer, effectively representing what it is I have been saying to you all, to no avail:



So thanks for stumbling onto that, sharing it and finally proving my point! :)

You may want to finally read up on this and actually learn it since it appears from reading a thread at AVSF that you're getting a similar RGBY Panasonic DLP very soon.  You may also want to actually discuss this with other real calibrators like Jason Dustal, Kevin Miller, Joel Silver, Kris Deering (although probably not since he ignored me reporting this too!), etc. whom have discussed this numerous times as well, since you (and many others) don't seem to want to ever listen to me.


I would appreciate you correcting your misinformed posts there at AVSF in the Older DLPs thread (quotes below), saying that it was me who was wrong, continuing to deface my name, especially when I can't reply back now, mostly due to similar misinformation and apparent lack of calibration knowledge.


Quote from: Javs
This is exactly what I measured on the lk990. It's colour volume is crap. Dave Harper told me the 970 didn't suffer it, quite adamantly at that but never substantiated it with measurements. It just shows he was wrong also.

On the lk990 you can turn off brilliant colour and measure correct values but the light output is 40% lower. Seems like you do indeed have brilliant colour hard coded on.

Everyone (mainly Dave)  was always telling me I was wrong. Thanks for showing I was not.

Sent from my SM-G988B using Tapatalk

Quote from: Javs
Yah, the bar is low given what the LK990 did, and to be frank, if its even similar, for the price its quite good.


Here is some additional info pertaining to this, as it relates to WRGB OLEDs which impart similar issues as RGBY Laser Phosphor:

https://displaycalibrations.com/lg_templates_for_device_control.html#What_is_the_'Peak_Brightness'_setting_and_how_it%E2%80%99s_affecting_the_LG_OLED_TV_luminance_output?



LG 2019 OLED TV's feature a 'Peak Brightness' control. The default setting for HDR10 mode of Peak Brightness is 'High', which will provide the highest panel peak luminance output when you will use it with custom PQ curve parameters values.


LG 2019 OLED Peak Brightness
Official BenQ LK990 Owners Thread



Peak Brightness control provide the capability to change the amount of White sub-pixel 'boost'.



The White sub-pixel can't be permanently disabled when you will set Peak Brightness at 'Off', but setting to 'Off' it will significantly reduce the panel peak luminance output.



While the peak output will be reduced, the color accuracy will be increased because saturation distortion will be reduced in the result of less color reproduction errors.



In a display, a 'pixel' is a collection of individual display elements that, when taken together, are able to reproduce the full-color range of which the display is capable.



The LG OLED WRGB displays implements white with target peak luminance higher than maximum luminance using three-color subpixels (W/R/G, B/W/R, G/B/W or R/G/B) among four-color (W/R/G/B) subpixels in order to adjust a color temperature.



In order to enhance the luminance of the LG OLED TV, especially for HDR mode, an additional a W sub-pixel (unfiltered transmitting white light) has been added to the other three sub-pixels (RGB) which are filtered.



The unfiltered White sub-pixels are much more efficient than the RGB-subpixels, so efficient drive schemes based to 'White Replacement algorithm' utilize the W primary as much as possible and the RGB primaries as less as possible, by computing and removing/subtracting the neutral luminance from an RGB triad of sub-pixels and transfer/assign it to the W sub-pixel, this method increases the overall efficiency of the display panel.



One recommendation you can test, when the maximum luminance (Peak Luminance value) of the LG 2019 OLED TV is 800 nits, to track PQ-EOTF as accurately as possible up to 540 nits (540 nits / 800 nits = 0.675). This will require to set the Roll-Off Point @ 68% value.



Another recommendation you can test, for reducing the color saturation distortion because of white sub-pixel 'boosting', is set 'Peak Brightness to 'Off' and then measure the Luminance of the display primary colors, using 10% Window (L32) patches with 100% Luminance level, then sum the Y (luminance) of primaries (Y of Red + Y of Green + Y of Blue) and after the summary, use that number as 'Peak Luminance' parameter value and apply 'hard-clip' by uploading 100% values to all 'Roll-Off Points'.



Doing that, you will preserve the maximum possible color accuracy and minimize any color saturation distortion effect while you will reduce your peak output and preserve a 'less-HDR-effect' as a negative side-effect.



To verify using that method that the display will perform closer to an additive display performance, where the sum of the luminance of a primary color will provide the same luminance as White, then you have to re-measure the W,R,G,B at peak luminance to verify that each primary can deliver the appropriate luminance level for your peak White brightness measurement.



To pass this test, the sum of the luminance of R, G, and B will be approximately equal to the luminance of White.



When the White luminance level is higher than the sum of the primaries, then the display is not performing as an additive.



When the White Luminance level is lower than the sum of the primaries, this likely means that there some luminance compression happening (e.g., power saving/management).



The accepted tolerance will be a luminance discrepancy of -1 to 5%.



EBU TECH 3320 (Version 4.1 - September 2019) - User Requirements for Video Monitors in Television Production, defines the technical characteristics for video broadcast monitors used in a professional TV production environment for evaluation and control of the images being produced.



From Version 4.0, it's been added a section dedicated to High Dynamic Range and Wide Color Gamut for UHD and 1080P HD Monitors.



That section splits Grade 1 HDR monitors into two types: Grade 1A HDR and Grade 1B HDR. A Grade 1A monitor can accurately reproduce all aspects of the standard it was designed to display.



A Grade 1B monitor may not be capable of reproducing the full range of color or brightness defined in a standard, but will otherwise fulfill all the requirements of a Grade 1A monitor.



This novel approach was taken to bridge the gap between what a video standard may define and what monitors currently available on the market are able to reproduce.



Grade 1B HDR monitors require ≥1000 nits peak white, but they can have reduced Gamut and limited brightness specifications. Grade 1B HDR may be withdrawn at a future date.



When a Grade 1B monitor is unable to display an input signal correctly, e.g., it cannot physically display colors conveyed in an ITU-R BT.2100 signal, it shall by default apply a hard clip of the linear display signals to the available color volume whilst maintaining the ITU-R BT.2100 white point, rather than applying a soft clip (roll-off).



For Grade 1A HDR PQ or the Grade1B HDR PQ monitors, a 199.2cd/m2 (code value 592, 10-bit full range) full screen, uniform field input signal shall be displayed without power limiting.



LG 2019 OLED TV's, unfortunately can't meet these specifications, and can't be recommended for color grading of HDR content.



But LG 2019 OLED TV's can be used as client view (review screening), onset, VFX, editing, or QC applications.



Re: Official BenQ LK990 Owners Thread
« Reply #13 on: August 27, 2020, 12:20:30 AM »
You may want to post there and mention it to the folks like tnaik4, SirMaster, 12GAGE, MDesigns, bdht, and yourself too, since they also seem to have it all wrong, except maybe SirMaster who seemed to be on the right path.


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If the narrower band wavelength of the Leds is causing the chromatic aberation i guess the lens isnt the deciding factor, the Lk970 has 93-94% rec709, the M150 has 90% Bt2020 so that is a huge difference lol, and might be causing it.


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I have tried calibrating 3 different LK970 multiple times, but I have never got more than ~64% rec709 gamut coverage.
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It's always super short in luminance, like 30-50% too low depending on the color and that leads to a coverage of only about 64%, despite the saturation and hue on the 2D CIE chart looking good.

Have you actually measured the LK970 at >90% rec709?


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Yes i measure it in calman, i can re-measure it now if ud like and share it here


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This is just now, With stock settings, normal laser.


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Hmm.  I mean yeah my 2D CIE looks just like that, but when it factors in the luminance, it falls way short.
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What are the luminance percentages of reference of the colors in your measurement?

I was using DisplayCAL to measure my gamut.

Do you get a similar gamut coverage after a 3DLUT?


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When i create 3dlut with displaycal or lightspace yes you are right it says 64-65% gamut. But how come is there that much difference between calman and lightsapce/displaycal.
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On the other hand my Sim2 M150 measures even better in Lightspace/Displaycal compared to calman where it already measures great to begin with.
I m getting 89.7% bt2020 stock settings , and 93-94% bt2020 in Lightspace/ Dispalycal so i guess every program measure it in its own way.


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The reason for the low gamut % with 3DLUT in DisplayCAL is because the luminance values are super low and the 3DLUT is trying to correct them but it physically can't because the projector just can't do it.
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I have never used CalMAN so I am not sure really much about what it's doing or reporting.

In your last picture, look at the Y vs. Target Y for your colors.  The Y is way too low compared to the target.  Remember, color gamut is a 3D volume, not just a 2D triangle.  You can reach way out to the proper "saturation" level of a color which you see on the 2D CIE diagram (x and y), but still be way short on luminance (Y), and the gamut coverage therefore shouldn't be considered 100% or close to 100% if the luminance is way too low.

[MEDIA=youtube]BQGbbobBsiw[/MEDIA]


You can have a 2D CIE that looks like the corner points are perfect, but still be way short on luminance.
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Ah i see , i guess the luminance on the LK970 is really lacking.
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I took another measurement of the sim2 m150 but with proper settings because it was just default before and as u can see now the color luminance is almost spot on.
This is with bt2020 and a 3dlut will make it exactly on point.
The LK970 on the other hand cant get the luminance close, i just tried and i guess its a limitation.


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Yeah your luminance values look fine.
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It's just some projectors such as the LK970 that fall way short for some reason.

I have seen the issue on a couple other DLPs as well.  Never seen it on an LCD or LCoS though.  But of course not all DLPs are like that at all, just some.

And yeah you should definitely check out the theater fan/wind project, it's really awesome.  Less gimmick than you might think (when done right).  Could use some more users.  I'm still improving and expanding things on the project.  I hope it can really take off more once I make the fans easier to use and more generic to support all video sources.


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Yeah, I will admit that I don't really know how the luminance is exactly supposed to play into the "gamut coverage" calculation and number.  I am no expert.
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But with the luminance values being so low, the actual vs. target colors (and deltaE 2000) are pretty far off and so I think perhaps the full gamut coverage is quite low, but again I am not sure exactly how to "properly" report that.


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I dont think 3chip dlp would have this problem and typically rgbrgb wheels do ok, its wheels other than rgbrgb or when the diodes arent to spec, like that panasonic pt-rz470(red and green leds with a laser/phosphor for green) has good red saturation but low luminance and less green saturation but luminance is too high.
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It sounds awesome im absolutely going to look into it. It didnt come across as gimmickery at all...  Tactile sensation and immersion is real.  A gimmick is like... 1,000,000 dynamic contrast!


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I think it happens on RGBW wheels.  Do we know if the LK970 is RGBW?  It's because the white part messes with the proper color luminance I think.


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I meant like is the LK970, 94% rec709, or is it 64% rec709?
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If you look at the chromaticity (x,y) and the 2D CIE diagram, it seems like it's 94% coverage.

But if you look at the luminance values for the colors on the LK970, they are far short, upwards of 50% short in the worst cases and this leads to large deltaE 2000 errors and leads software like DisplayCAL to give you a number like 64% rec709 coverage when measured.

I am not sure how this gamut coverage number is exactly supposed to be calculated and reported and how the luminance should be factoring in.


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there are tactile transducers/bass shakers which provide rumble and dbox which has lift roll yaw pitch motion.  I have to temper my subs response so i isolate them off the floor with sorbothane then use bass shakers to replace the tactile rumble.  Works really well for preventing low frewuencies from getting out of the room, persons with sub bass sensitivity, while still providing good immersive feedback.
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Would love to incorporate dbox and wind, but dbox wont work, so the idea that i can add wind is really cool...


not sure, there are an array of color wheels and in some instances 2 color wheels.  rgbcym, rgbcy(which is what led overlap does), rgbw, rgby, rgbrgbg orsometimes a dark green segment for p3 gamut.


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Blue core lasers are typically RGBY, so I think the 970 is similar.


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Actually I think the LK970 is RBGY and the LK990 is RGBW so the LK990 might be even worse.
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I think it also has to do with BriliantColor on the LK990 because with that off color accuracy is good, but the brightness is very low, lower even than the LK970.  With BriliantColor on the color is not able to be calibrated to any sort of low dE.


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Its one of the reasons why i get posterization when doing a 3dlut on the LK970 , its very obvious,  the sim2 doesnt have any at all.
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I think its the main reason why the sim2 look bright, cause it has a lot of range for color luminance .


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Yeah I do think it's why there is so much posterization.
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Because it's trying to take a 64% rec709 to a 100% target.

I did find that using a different rendering intent in ArgIICMS minimizes the posterization by a lot, and guess what that rendering intent does / is called...

“Luminance preserving perceptual” (ArgyllCMS 1.8.3+) uses compression to make the source gamut fit within the destination gamut, but very heavily weights the preservation of the luminance value of the source, which will compromise the preservation of saturation. No contrast enhancement is used if the dynamic range is reduced. This intent may be of use where preserving the tonal distinctions in images is more important than maintaining overall colorfulness or contrast.

I don't think it's a coincidence that the rendering intent that sacrifices saturation for luminance and that uses compression produces the best result on the LK970.


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The thing is also when i do a p3 3dlut with my jvc rs440 whcih does 90%p3 i get posterization but to a lesser degree than the LK970, a lot less actually but its there and can be seen in some scenes.
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With the Sim2 M150 i create a bt2020 3dlut and no posterization whatsoever even though the projectoe can do 90% bt2020 not 100% , i guess the RGB LED is a different animal.
There is a workaround in LightSpace called Concatenation method, and DisplayCal also has good solution for it but at the expense of saturation like u said, i just dont know how come the Sim2 has absolutely zero posterization.


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I talked to someone who is much more knowledgeable on 3DLUTs about it once before and they said posterization is not really caused by targeting a larger than native gamut.
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For example I tested targeting P3 on my rec709 PC monitor which only does about 78% P3 and I saw no posterization with the P3 3DLUT.

It's definitely more complicated than that, but unfortunately is past my current understanding of color systems.


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This is exactly what I measured on the lk990. It's colour volume is crap. Dave Harper told me the 970 didn't suffer it, quite adamantly at that but never substantiated it with measurements. It just shows he was wrong also.
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On the lk990 you can turn off brilliant colour and measure correct values but the light output is 40% lower. Seems like you do indeed have brilliant colour hard coded on.

Everyone (mainly Dave)  was always telling me I was wrong. Thanks for showing I was not.

Sent from my SM-G988B using Tapatalk


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If I had to describe it based on trying to calibrate 3 LK970 both manually and with 3DLUT, I would definitely describe the behavior resembles that of BriliantColor and what happens when you have a RGBY or RGBW color wheel.
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I also encountered the same behavior with this projector:  https://www.projectorcentral.com/Optoma-ZH403-1080p-Laser-Projector-Road-Test.htm"]Optoma ZH403 1080p DLP Laser Projector Road Test[/URL]


It had far-off luminance, but with BriliantColor off I could get low dE, but at less than 2000 lumens on a 4000 lumen spec machine.
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On the 970, I am not surprised that BC is hard-coded in. My thought was that BC was always there and adjusted to provide more brightness for the LK990. Once you have seen or measured enough units you can spot BC a mile away. I can see it in the rendering of whites. RGB Laser or high lumen LED is the path forward for DLP in my opinion.


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BrilliantColor, amazing name for a feature that f**ks up colors! :cool:
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I believe my Hitachi RGB LED DLP has something similar baked in to the different light source powerlevels. I am still waiting answer from Hitachi to tell me how those should work. In my testing the Low-setting is the only usable one with good colors with proper luminance, mid and high settings boost the whites, but color luminance goes dimmer than the Low-setting!


I guess there's a reason we all aren't engineers for these things! ;D
« Last Edit: August 27, 2020, 04:52:36 AM by HarperVision »

Javs

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Re: Official BenQ LK990 Owners Thread
« Reply #14 on: August 27, 2020, 02:51:21 PM »
You can think what you like. You are just going around in circles, the colour volume is not going to be fixed by some software setting, you are admitting they boost saturation to make up for it, this doesnt change a thing. I am really uninterested in fueling your passive agressive posts as there is no end in sight to them unless you are willing to start over. 

Yes I did buy that projector yesterday, its better than the BenQ LK990 I had here, yes it does still have the 'brilliant colour' thing, it also has a larger gamut natively, and yes I measured its luminance errors easily, its got better dimming, its far brighter, I can tone map HDR properly on it, you can actually select the gamma properly etc etc The only thing is its 1200p. Calman is not the only calibration software in the world by the way. I will keep it because it cost a small amount for what it was originally worth, only about $2000usd for a 39hr unit. Good for a play anyway and maybe for the family room in the future.
« Last Edit: August 28, 2020, 07:22:44 AM by AVSMike »
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