BENQ/ASUS 120Hz+ Easy LightBoost hotkey app on AMD/nVidia! (Strobe backlight. Zero motion blur. Bett

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Nope. It's not eyestrain, it's simply having vision issues for a brief period after.

I'm not sure I like the authoritative talk about this method of using LightBoost like it's been around for years. As far as I can see this implementation is pretty new and untested.
What authoritative talk? I am not talking about LightBoost. I never said it was around for long.

But you surely know old TV's flicker (strobe) a lot. Lots of existing talk about vision issues, some 50 years old about eye strain and issues after watching television. Many search phrases exists, such as "television hurts my eyes". Some say it's not a big issue, other say otherwise, but the debate has existed for a long time. Research have leaned towards conclusions on both sides of the fence for a long time.

Strobe displays have been around for almost a century, back to the day that Baird broadcast television almost 100 years ago from Crystal Palace to Nipikow disc television receivers with an image that strobed at a mere 16 Hertz. Long before CRT's replaced them. Even today, CRT are strobe displays too. Many flicker madly, especially older 50 Hz or 60 Hz ones.

CRT's were invented in the early 20th century, and have been around for a long time. As televisions gradually became popular in the 1960's and 1970's, it was noticed that there can be eyestrain in darker rooms and at closer viewing distances. Leading to the tales about TV's killing eyes in a dark room (maybe an exaggeration, although it indeed stresses the eyes more). In the UK, the 50 Hz flicker is famously annoying and that is why there are 100 Hz and 200 Hz televisions. Vision problems / eyestrain / etc from long-term watching of CRT, also depends a host of factors, the human, the picture brightness, the room lighting, how close you're watching, etc. Sitting right up close to a CRT computer monitor in a darkened room, can also amplify the problem. Also, some people are used to CRT for so long, but then stop using CRT's (and use LCD's which are sample-and-hold displays), and are not used to CRT.

Some people have well-documented (chiefly temporary) vision-related issues (strain/issues/etc) after watching TV at close distances for long periods, especially on older 50 Hz CRT's in the UK. Not everyone, but some. That in itself, is well-known. The same knowledge would easily apply to new strobe backlight technologies. Flicker (strobing) can be a double-eged sword; it massively reduces motion blur but it can also annoy people.

Some people cannot tolerate the flicker of older fluorescent lights, and prefer newer flicker-free fluorescent lights. That in itself, is also well-known.

Also, it is well known some people can't tolerate 3D shutter glasses either (which has worse eyes effects than just using LightBoost, for example, since the flicker is now 60Hz per eye, instead of 120Hz per eye). After all, LightBoost was originally designed for 3D -- but you'll only get 60 strobes per eye, instead of 120 strobes to both eyes. That in itself, is also known, although a new area of research, but boils down to the flicker issue. nVidia even includes a warning in their 3D Vision manual for prolonged 3D exposure to rest your eyes. The same warnings applies.

Lots of scientific research over decades made the following recommendations for TV watching, back in those days when televisions used to flicker a lot:
-- Adequate distance from CRT
-- Appropriate CRT brightness
-- Environment not too dark
(modern recommendations about computer monitors often suggest putting some rear lighting, such as a small lamp behind the monitor)

I will eventually clarify my FAQ's to include some of this well-known information. That said, there are now many kids today who has never used a CRT, and may not be aware of this formerly widespread information.
 
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Not really concerned with strobing backlights but more using LightBoost in this manner.

Never had issues with any screen display types prior and the effect the LightBoost method had on me has never been experienced before.
 
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Not really concerned with strobing backlights but more using LightBoost in this manner.
Never had issues with any screen display types prior and the effect the LightBoost method had on me has never been experienced before.
Interesting --

It depends on what your vision issue or eyestrain (etc) is caused by. There are minor differences in flicker behavior: CRT has a phosphor decay while LightBoost turns on/off instantly, though it could be softened using a capacitor decay (in future models -- possibly a suggestion to nVidia). During videogames, three people reported less eyestrain with LightBoost than without, because of zero motion blur. Also, some people who have stopped using CRT for years, having to put a CRT monitor on their desk again, need time getting used to it. You can turn on/off LightBoost after exiting games.

Although several reported eyestrain or vision issue, others reported none.
I had some VERY surprising reports that someone had less eyestrain playing videogames with LightBoost than without.

But this isn't applicable to everyone.
More game usage? (moving images)
More desktop usage? (static images)
Are your eyes bothered more by flicker?
Are your eyes bothered more by motion blur? (focussing muscles getting tired tracking objects that look out-of-focus)
....Everyone seems different!

Including this person from HardForum:
2d Lightboost has less eye strain than when my LED monitors are in default mode.
But you are right, some people (albiet not everyone) DO have eyestrain or vision issues with LightBoost. Also if it is not eyestrain (for you) but a simple vision color issue, it *might* also be because the BENQ monitor reportedly has a crimson color when using LightBoost. That means your eyes' color temperature is adjusted to a crimson-tinted computer monitor, which means when you step away from the monitor -- the whole world looks greenish-colored for a few minutes (green is the negative color of crimson/magenta). Thus, it's important to determine what vision issue you are having, so that the appropriate warning labels can be added to my website in the future (even though nVidia has already warnings in their instruction manual).

Check out Negative Afterimage Optical Illusion or google "Complementary Color Optical Illusion". Determine if it's the cause of your vision issue with BENQ LightBoost. It also happens if you've been indoors in a windowless incandescent-lit room all day, then suddenly go outdoors. Everything outdoors looks a different color for a while. Same kind of effect. Maybe that's not what happened to you, but let's "make sure" that I rule this out, by posting a Crimson Fix, "just in case". That will allow us to rule out the complementary color effect, at least, next time it happens to someone...

Obviously you prefer it without LightBoost, but I shall try to help out others who still prefer LightBoost -- there are still indeed complaints about the BENQ's crimson color issue during LightBoost (possibly a tinting to compensate for greenish-colored shutter glasses)
 
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The BENQ XL2411T Crimson Fix

Zero crimson tint with BENQ LightBoost!
On the subject of BENQ color calibration, I cancel out the crimson tint via nVidia Control Panel, by doing the following:

Via Monitor Menus
Monitor's Contrast Setting = 65 .... (If using nVidia Gamma 1.10)

Via nVidia Control Panel - "Adjust Desktop Color Settings"
Adjust them individually, R, G, B.
---
R Contrast = 30%
G Contrast = 45%
B Contrast = 30%
---
R Brightness = 10%
G Brightness = 40%
B Brightness = 10%
---
R,G,B Gamma = 1.10

Make sure to readjust Monitor OSD contrast everytime you change Gamma. nVidia Gamma 1.10 worked best with a monitor OSD Contrast of 65.
With these settings, I can see the difference between RGB(0,0,0) and RGB(1,1,1), without a wrongly tinted color in backgrounds or in dim colors.

Test Patterns Used
-- Lagom Contrast Pattern
-- Lagom Black Level
 
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I seem to have run into another problem with lightboost - I can no longer turn it off. Unchecking enable stereoscopic 3D and selecting display in 3D mode "only while 3D programs run" or "only when full-screen 3D programs run" will not turn lightboost off. It also sets itself to use lightboost on startup.
 
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Thanks Mark! The colors will then only be fixed during desktop use isn't it? The nVidia desktop settings do not effect the ingame colors.

That is correct for some games. Others will use the Nvidia settings but overlay them with their own gamma curve information which can be undesirable as far as colours go. It should still correct the obvious Crimson tint or at least improve it. Unfortunately this is the kind of sacrifice you have to make using LightBoost for something it wasn't really intended for (2D).
 
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I seem to have run into another problem with lightboost - I can no longer turn it off. Unchecking enable stereoscopic 3D and selecting display in 3D mode "only while 3D programs run" or "only when full-screen 3D programs run" will not turn lightboost off. It also sets itself to use lightboost on startup.

I had the same issue. Forcing it to 144Hz, shutting down the PC and monitor and then back to 120Hz solved the problem.
 
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That is correct for some games. Others will use the Nvidia settings but overlay them with their own gamma curve information which can be undesirable as far as colours go. It should still correct the obvious Crimson tint or at least improve it. Unfortunately this is the kind of sacrifice you have to make using LightBoost for something it wasn't really intended for (2D).
As you're PCM, I want to make the following recommendations to future monitor manufacturers.

A Preliminary Public Call To Monitor Manufacturers

Past strobe backlights were mostly worthless (e.g. year 2006 BENQ "AMA-Z" that flickered annoyingly at 60Hz and reduced motion blur by only a few percent). Monitor manufacturers are kind of leery about strobe backlights ever since then. What has changed is that today's strobe backlights are vastly superior and yield a rather huge motion blur elimination (when used with panels that can virtually completely erase pixel persistence between refreshes) The cost:benefit ratio has changed dramatically to the point where this is finally a worthwhile (and "free") feature that can also be built into existing 3D monitors.

Monitor Picture Adjustments Are Disabled During LightBoost
These are presently the assumed reasons why this is happening:
(1) Precisely calibrated response-time compensation (pixel response acceleration technologies) is necessary for maximum compatibility with strobe backlights, for correct timing of strobe backlight in the pixel response curve. This often requires blacks and white points to be precisely limited.
(2) Enabling picture adjustments in the monitor can interfere with the RTC curve, and cause crosstalk problems.
(3) Contrast ratio is greatly reduced during LightBoost.
-- The black level is often bumped up slightly above true LCD black level. (This can optimize RTC efficiency for full BTW / WTG pixel transitions.)
-- The white level is often bumped below true LCD white level. (ditto).
(4) It's possible this is part of an nVidia recommendation, especially from earlier models of LightBoost monitors that had poorer 3D crosstalk.
(5) Brightness can't be adjusted, but you can still control backlight brightness via the LightBoost pulse length ("LightBoost" adjustment). Lower LightBoost settings (other than "OFF") results in shorter pulses and even sharper fast motion.
(6) Fewer user complaints. People just want 3D Stereoscopic to work, with maximum image quality.

This May Be An Obsolete Approach Now
(1) Today's 1ms monitors such as BENQ XL2411T is now more forgiving for picture adjustments during LightBoost. Give a little more flexibility, please, nVidia & BENQ & ASUS. Some of us can understand the tradeoffs, and share recommended settings.
(2) Provide a simple preset for color compensation (e.g. adjust crimson tint)
(3) There are more and more new motion tests coming, which will help make it easier and more popular for consumers to demand better motion blur reduction. It becomes a necessary selling feature to optimize strobe backlight to also work during 2D.
(4) nVidia might not prefer it to be called "LightBoost" (because it does not "boost" light brightness during 2D use), but perhaps call it "CRT Emulator" or "Zero Motion Blur Mode" or "Strobe Backlight"
(5) If interference with RTC is a concern, permit an Advanced Mode that re-enables picture adjustments during LightBoost, with a "WARNING! This will degrade stereoscopic 3D!"
(6) Improved education and advertising. The Blur Busters Blog is helping out here, the world's first web blog exclusively focussed on on LCD motion blur elimination technologies! The upcoming motion tests (easy Mac/PC compatible PixPerAn replacement) will revolutionize user education. My motion tests even allow the human eye to see improvement from 0.5ms strobes versus 1.0ms strobes versus 2.0ms strobes, so manufacturers need to be warned that they need to step up their game!

Recommendations To Monitor Makers For The Future
(1) Easier 2D usage of strobe backlight
(2) Allow shorter strobes (1.0 or even 0.5 millisecond strobes, pretty please!)
(3) Even brighter LED's. (to prevent ultra-dim picture during short strobes)
(4) Higher CRI LED's. (for better color)
(5) In PWM mode, include capacitor filtering to eliminate PWM eyestrain during dimmer screen modes.
(6) Allow us to adjust colors
(7) Allow us to adjust blacks fully to fullest LCD black.
(8) Allow higher Hz (e.g. LightBoost at 144Hz). This will start to affect crosstalk, but the new 1ms panels are now fast-enough-again that 144Hz strobed should be fine without objectionable crosstalk. 72Hz-per-eye will be a big improvement for 3D glasses.
(9) In higher end models, include a decay-softener. Capacitor to soften out the PWM pulses, whenever LightBoost is not used. This is pretty cheap to add to a high-end 120 Hz monitor. Less eyestrain during 360Hz and 432Hz PWM.
(10) (OPTIONAL) If all of this is unappealing, please at least include an API that allows this to be adjusted. e.g. publicly published custom VESA DDC/CI custom MCCS commands to allow us to write 3rd party applications to reprogram the strobe backlight behavior -- we've trying to search for the command now from VESA MCCS Version 3 using softMCCS. That way, advanced users can download the utility to customize this feature without confusing the everyday users of the monitor with very confusing OSD menus.

Obviously, nVidia probably has to be onboard because it's a collaboration between nVidia and monitor manufacturers. This represents an early (preliminary) public call to monitor manufacturers that will become louder once I've released my motion test software app (21st century PixPerAn replacement), which will probably gradually increase end-user demand for zero motion blur gaming LCD's that are as flicker-free as possible. (pcmonitors.info has early beta access to it now)
 
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[...]
Monitor's Contrast Setting = 65 .... (If using nVidia Gamma 1.10)

Via nVidia Control Panel - "Adjust Desktop Color Settings"
Adjust them individually, R, G, B.
---
R Contrast = 30%
G Contrast = 45%
B Contrast = 30%
---
R Brightness = 10%
G Brightness = 40%
B Brightness = 10%
---
R,G,B Gamma = 1.10

Wow, I just tried your settings, and our monitors are not identical at all. I use these settings:
R Contrast = 30%
G Contrast = 35%
B Contrast = 32%
---
R Brightness = 17%
G Brightness = 20%
B Brightness = 15%
---
R,G,B Gamma = 1.09 (only able to choose this or 1.11, not 1.10). Lightboost on and Contrast on 65 in OSD. Where you have to boost your green, the colours on my monitor are more balanced as it seems.
 
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Wow, I just tried your settings, and our monitors are not identical at all. I use these settings:
R Contrast = 30%
G Contrast = 35%
B Contrast = 32%
---
R Brightness = 17%
G Brightness = 20%
B Brightness = 15%
---
R,G,B Gamma = 1.09 (only able to choose this or 1.11, not 1.10). Lightboost on and Contrast on 65 in OSD. Where you have to boost your green, the colours on my monitor are more balanced as it seems.
You can adjust gamma to 1.10 by using the arrow keys. Click the slider, then use the cursor left/right.

Very interesting you had to use very different values.

One way I discovered the bottom greyscale clipping point (for each color component) was to go to Lagom Black Level. As an example, temporarily slide "B Gamma" to maximum. Your background should remain completely solid black RGB(0,0,0) .... while the dim gray RGB(1,1,1) should now become brightly blue colored. If I go to 32, my clipping point changes, so I use 30, but obviously, adjusting Brightness affects Contrast, and vice-versa, so I have to keep adjusting until I get the black clipping and white clipping right.
I optimized for maximum uniformity and backlight brightness rather than ideal color temperature.

I wonder what is different between our monitors to lead to the different adjustment results, but I do observe that we both adjusted R and B to roughly similar values. Perhaps it was a matter of preference (overall color appearance, etc). What's strange is that our G is so different.
 
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Those are some crazily large adjustments to the default colours. I can't believe it looks anywhere near calibrated.

Remeber that this is with Lightboost on. Lightboost really washes the colours out. What I also noticed that my settings with BF3 are not all that good (to go back on my previous remark: nVidia Desktop settings effect BF3 colors). The colours in BF3 are nicely saturated (perhaps too much) but the darks are too dark, you can't see a thing, turning lightboost to max. doesn't help.

The difference between the monitors seems strange but with Mark's settings it was as if I was looking at a artist impression (Any Warhol?) of my desktop.

You know what? I'll make some photo's this evening of my monitor with both settings, then you can see what I mean. I'll post them here.
 
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I had the same issue. Forcing it to 144Hz, shutting down the PC and monitor and then back to 120Hz solved the problem.

I'm actually using the 20t not the 10t. Shutting down totally doesn't seem to reset the monitor to normal mode anymore. It has become stuck in lightboost mode. I like being able to use lightboost but I don't want it forced on the entire time.
 
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Ok, pictures are not a success. I know also did the clipping test with the Blacklevel Lagom Test:

R Contrast = 27%
G Contrast = 30%
B Contrast = 35%
---
R Brightness = 35%
G Brightness = 35%
B Brightness = 37%

I'm quite lost with this and apparently not an artis good with colors.
 
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The BENQ XL2411T Crimson Fix

Zero crimson tint with BENQ LightBoost!
On the subject of BENQ color calibration, I cancel out the crimson tint via nVidia Control Panel, by doing the following:

Via Monitor Menus
Monitor's Contrast Setting = 65 .... (If using nVidia Gamma 1.10)

Via nVidia Control Panel - "Adjust Desktop Color Settings"
Adjust them individually, R, G, B.
---
R Contrast = 30%
G Contrast = 45%
B Contrast = 30%
---
R Brightness = 10%
G Brightness = 40%
B Brightness = 10%
---
R,G,B Gamma = 1.10

Make sure to readjust Monitor OSD contrast everytime you change Gamma. nVidia Gamma 1.10 worked best with a monitor OSD Contrast of 65.
With these settings, I can see the difference between RGB(0,0,0) and RGB(1,1,1), without a wrongly tinted color in backgrounds or in dim colors.

Test Patterns Used
-- Lagom Contrast Pattern
-- Lagom Black Level

I found these settings looked too green on my XL2411T.
I used these settings instead:

Mon contrast 65
Nvidia settings
Gamma 1.15

Red B 30 C 15
Green B 35 C 30
Blue B 25 C 10


Does anyone have an inf that will let the monitor run at 144hz with lightboost on yet?
 
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Just tried this on my Windows 8 PC and when I hit apply in the Nvidia control panel to enable 3d it gives me a BSOD quoting the Nvidia driver.

I'll try a clean driver install later but anyone else had this?
 
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so let me get this sorted.

only NVidia lightboost can change my monitors backlight to create this effect? No ati card can control this backlight to create the same effect?
 
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so let me get this sorted.

only NVidia lightboost can change my monitors backlight to create this effect? No ati card can control this backlight to create the same effect?

That is correct. Untill someone hacks it there is no support to enable lightboost with an AMD card.
 
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