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

[Mark Rejhon]

ADDENDUM -- NEW OCTOBER 2013 METHOD
Easy ToastyX Strobelight App -- hotkey utility -- turn ON/OFF LightBoost via a key press! Now works on both AMD and nVidia.

Based on instructions from:
www.blurbusters.com/zero-motion-blur/lightboost

Zero motion blur on LightBoost LCD's
"looks like CRT"

- Makes ASUS/BENQ 120Hz monitors have less motion blur than CRT
- Eliminates all ghosting, all motion blur
- Enables LightBoost strobe backlight even in 2D mode.
- Strobe backlight bypasses pixel transitions (keeps pixel transitions in dark, strobe after pixel transitions)
- Confirmed. several third party confirmations! "It looks like my old CRT" (etc)
- Video: High speed video of LightBoost and the Science + References Page
- LightBoost Media Coverage by AnandTech, ArsTechnica, NewEgg, ASUS

Check this out:

TFTCentral.co.uk has tested LightBoost with their equipment and found LightBoost outperforms all past scanning backlights they have ever tested, including the old BENQ AMA-Z and Samsung MPA from 2006.

Check out TFTCentral's Motion Blur Reduction Backlights article!

_________

Easy LightBoost: Completely Eliminate Motion Blur on 120Hz+ Monitors

List of Supported 120Hz and 144Hz Monitors
Currently Supported Monitors: ASUS: VG248QE, ASUS VG278H, ASUS VG278HE, BENQ XL2411T, BENQ XL2420T, BENQ XL2420TX, BENQ XL2420TE, BENQ XL2720T.

-- Easy LightBoost via ToastyX Strobelight App
-- Easily turn ON/OFF LightBoost via a keypress! No hacks. No registry tweaks.
-- Also works on 3-monitor surround setups. Does not require 3D Vision drivers.

1. First, Download ToastyX Strobelight.
   IMPORTANT: You must have a supported 120Hz ASUS or 120Hz BENQ monitor!
   DO NOT INSTALL STROBELIGHT IF YOU DO NOT HAVE A SUPPORTED MONITOR.
   .
2. Next, run strobelight-setup to install strobed video modes. Then reboot.
   
   
   ...
   
   
   IMPORTANT: To easily turn ON/OFF LightBoost, you must install at least one strobed refresh rate AND at least one non-strobed refresh rate.
   .
3. Finally, after reboot, run strobelight to initialize LightBoost for the first time.
   NOTE: You can add strobelight.exe to the Startup Folder, so it starts up everytime you starts Windows.
   .
4. Test LightBoost using a motion test. View Moving Photo Test at TestUFO.com.
   Turn ON/OFF LightBoost while viewing this motion test to see the big difference.
   Test in Opera 15+, FireFox 24+, Chrome or other 120Hz-friendly web browser.

Useful LightBoost Tips

• Turning ON/OFF LightBoost via hotkeys
  Control+Alt+Plus -- turns ON LightBoost
  Control+Alt+Minus -- turns OFF LightBoost
  .
• Other Ways to Verify that LightBoost is enabled:
  (a) Check monitor OSD menus. The "LightBoost" adjustment should be unlocked.
  (b) Wave a finger in front of a white screen. You should see a stroboscopic effect.
  (c) Use a motion test such as www.testufo.com.
  Turn ON/OFF LightBoost while repeating test, to see the big difference.
  .
• For better LightBoost colors, adjust your nVidia Control Panel:
  nVidia Control Panel Desktop Brightness = 52%
  nVidia Control Panel Desktop Contrast = 45%
  nVidia Control Panel Desktop Gamma = 0.70
  This compensates for the LightBoost gamma bump (washed out colors).
  NOTE: If you get a purple tint, lower the Contrast setting via monitor's menu until tint disappears. You can also adjust while viewing the Lagom Contrast Test Pattern.
  .
• For optimal benefit, run your games at triple-digit frame rates.
  Microstutters become easier to detect if they're no longer masked by motion blur. To eliminate stutters, run LightBoost at frame rates matching the refresh rate.
  (a) Run at 100fps @ 100Hz, or run at 120fps @ 120Hz.
  ...Adjust game details or upgrade your GPU. Also try FXAA instead of FSAA.
  (b) Experiment with VSYNC ON (may lag) or use "Adaptive VSYNC" (less input lag)
  ...These settings makes LightBoost framerate=Hz motion look much smoother, to allow game turning/strafing panning motion as smooth as TestUFO or PixPerAn.
  (c) Use a good 1000Hz gaming mouse.
  ...Mouse microstutters can hurt motion clarity. LightBoost benefits from a mouse that can turn left/right as smoothly as keyboard strafing left/right.
  .
• For other information, see the LightBoost FAQ.
  If you are unable to turn off LightBoost, simply re-run strobelight-setup.exe and install non-strobed refresh rates. Alternatively, simply unplug your monitor's power cable for a few seconds to deactivate LightBoost.

How is it possible?
--> LightBoost is a programmable strobe backlight stays turned off while waiting for pixel persistence. The pixel transitions are kept in total darkness, and the backlight is strobed only after pixel transitions are finished. This bypasses pixel persistence as the motion blur barrier. (Proof: high speed YouTube video of a LightBoost strobe backlight) The strobe lengths are only 1 milliseconds long on the BENQ, and it was recently measured to eliminates of 94% motion blur (1ms out of 1/60sec) relative to a common 60Hz LCD, and eliminates 85% of motion blur (1ms out of 1/120sec) relative to 120Hz LCD's.
--> List of supported 120Hz monitors can be found at List of 120Hz Computer Monitors

CRT style gaming on LCD
It is CRT sharp; allowing complete immersion without being distracted by motion blur. You do need a GPU fast enough to frequently hit 120fps@120Hz most of the time to really notice the big improvement in motion clarity, with perfectly clear images even during fast turning. Also, disable the GPU artifical motion blur effects in video games, as that reintroduces motion blur that you've zero'd out with this strobe backlight tweak. Also, some source-engine games needs their fps_max raised at the developer console, to play smooth. Also try turning VSYNC on versus off, since some games play more smoothly with one or the other setting (game-dependant). If you are a big-time gamer that plays lots of TF2 or Quake Live, or other fast-twitch action games, the CRT-style motion clarity more than outweighs the other side effects.

Overclockers.uk BENQ monitors
As a courtesy to the people of Overclockers.uk, I'm referencing this site's own purchase pages:
BENQ XL2411T on overclockers.co.uk
BENQ XL2420T Rev2 on overclockers.co.uk

Thanks
Mark Rejhon
BlurBusters.com Blog -- Eliminating Motion Blur On LCD's

ADDENDUM -- NEW OCTOBER 2013 METHOD
Easy ToastyX Strobelight App -- hotkey utility -- turn ON/OFF LightBoost via a key press!

Based on instructions from:
www.blurbusters.com/zero-motion-blur/lightboost

 

[Mark Rejhon]

P.S Any chance you can get the EDID for the Benq XL2420XT

There's one for the XL2420T near the bottom of page 1 of this thread:
http://3dvision-blog.com/forum/viewtopic.php?f=14&t=2025

 

[Mark Rejhon]

Sadly as excited as i am to get my eyesight back in games its still a TN panel with a crimson tint? It makes me incredibly unhappy knowing the colors still get messed up and i simply cannot give up my ips colors even if it is for no motion blur.

The technology already exists for IPS, with a big "but...."

Some Sony and Samsung HDTV's (which use IPS) use a scanning backlight, which does a similar thing. (Examples of existing HDTV's with scanning/strobe backlights) Those are great for fast-action sports/documentaries/olympics/racing/etc. Unfortunately, for games, those add a lot of input lag, and sometimes is combined with interpolation, and those are not video game friendly. In addition, using them without interpolation, means 60Hz flicker -- which is annoying (like a 60Hz CRT)

The LightBoost strobe backlight is the first that I know of, that uses strobe lengths short enough (~1ms flashes) to reasonably compete with CRT phosphor illuminate-and-decay (~1ms total), WHILE also being near-zero-lag and video-game compatible. And at 120Hz, it does not flicker to most eyes. So LightBoost strobe backlight monitors, appear the most accurate CRT emulators, without the 60Hz flicker disadvantage, and without the input lag disadvantage. Alas, current LightBoost models are TN panels.

For now, we still need to pick our poison (LightBoost+TN) if we want CRT-style zero motion blur in an LCD panel today that's in a video game compatible manner (negligible input lag).

 

[Mark Rejhon]

Although I personally won't use this (not interested in any 3D/120hz panels) this is pretty darn cool ^^

You don't need to use the 3D feature of a 3D monitor.

The 3D is just simply a good pre-requisite. This is because 3D panels are designed to prevent pixel persistence from leaking too much into the next refresh. That allows clear frames for shutter glasses operation -- and as a side effect, also permits strobe backlight on clear fully-refreshed frames.

That said, I agree with you about TN. The color quality of TN leaves some to be desired. It's certainly possible for the technology to arrive with IPS, but there are no IPS 120Hz displays available.

 

[Mark Rejhon]

Taking delivery of 2 more xl2420ts on tuesday so keeping an eye on this.

This tweak also works on XL2420T, though, I heard that the XL2411T has a brighter LightBoost with shorter strobe lengths. This may explain why the XL2411T is rated at a 1ms pixel response time.

(Incidentially, LightBoost apparently helps improves the accuracy of pixel response time claims, by hiding pixel persistence from the human eye, as shown in the high speed video -- so reportedly, the "1ms" response is actually more honest than expected, thanks to the strobe backlight with 1ms strobe flashes)

 

[Mark Rejhon]

EDIT: To be fair it does seem to be reducing over-drive overshoot on some stuff i.e. bright colored spherical objects no longer have a slight black halo on fast moves but its a marginal improvement tho not an unwelcome one.

EDIT2: Playing QuakeLive 125fps/120Hz again minor increase in image stability on fast view changes, this panel is already pretty decent for it tho so maybe shows a bigger improvement on the 11T.

Thanks for your reports. Most of the testimonials I've gotten are for the ASUS, since apparently turning on LightBoost on the ASUS has a bigger impact than turning on LightBoost on the BENQ does.

Some preliminary tests show true measured MPRT ("Motion Picture Response Time") measurements improving from 7.7ms to 2.0ms on the ASUS VG278H (almost a ~75% reduction in motion blur relative to non-LightBoost 120Hz), but on the BENQ, the MPRT was already 2.2ms and improves to 1.0ms on the XL2411T (only about a ~50% reduction in motion blur relative to non-LightBoost 120Hz)

 

[Mark Rejhon]

Pretty much inline with what I found then - the difference from almost 8ms down to 2ms would be very apparent (average person can detect a change in light levels lasting around 1/200th of a second) - but very few people would notice changes once you go below ~2ms (only top fighter pilots, etc. able to detect differences at around 1/500th).

Actually, the average enthusiast gamer would be able to use a motion test pattern (e.g. PixPerAn) to tell the difference between 1ms and 2ms strobes.
For a motion of:

960 pixels/sec (16 pixels step per frame) @ no strobe = 16 pixels of motion blur.
960 pixels/sec (16 pixels step per frame) @ 50% strobe (8ms) = 8 pixels of motion blur.
960 pixels/sec (16 pixels step per frame) @ 25% strobe (4ms) = 4 pixels of motion blur.
960 pixels/sec (16 pixels step per frame) @ 12.5% strobe (2ms) = 2 pixels of motion blur.
960 pixels/sec (16 pixels step per frame) @ 6.75% strobe (1ms) = 1 pixels of motion blur.

It is subtle though. However, you do not need to be a military fighter pilot to tell the difference. The humans aren't seeing the light flashes, but are seeing the retinal blurring caused by eye tracking.

 

[Mark Rejhon]

ADDENDUM -- UPDATED INSTRUCTIONS ON WEBSITE
We found an official vendor-supported method to do this, without registry tweaks or INF files! However, the vendor-supported method does require you to have the 3D shutter glasses emitter. The new instructions works with all ASUS and BENQ LightBoost monitors:
www.blurbusters.com/zero-motion-blur/lightboost

 

[Mark Rejhon]

I agree, they go slightly washed out / as if a very very transparent grey film has been put on the screen. I personally don't really notice the difference, I've never noticed the blur. I'll stick to having my colours there

Yes, we've noticed that this is a LightBoost artifact; colors do degrade somewhat. It's more a problem at the Windows Desktop than in the videogames. Personally, I love the zero motion blur effect. All the blurring/trailing/ghosting/coronas completely disappear too on the XL2411T, while having zero motion blur!

It depends on the person; some people are really, really sensitive to motion blur.
The good thing about strobe backlights (LightBoost) is it's an adjustable feature -- you can turn that feature on/off.

 

[Mark Rejhon]

This is the result: http://i.imgur.com/9P50U.jpg

Very impressive.
Zero ghosting, zero motion blur, zero coronas, zero trailing.
If you have a magnifying glass, there is an ultrafaint renmant (less than 0.5%)
...but it is below human eye detectability without a magnifying glass!!

However, that said, a more accurate method to measure motion blur
is a pursuit camera (Tracking camera). A moving camera simulates a moving eyeball,
and more accurately captures WYSIWYG motion blur.
Here's an example:
Static camera versus tracking camera comparision

...

Static cameras are good for capturing pixel persistence effects.
Moving cameras are good for capturing WYSIWYG motion blur
including eye-tracking-based motion blur (the major cause of motion blur on LCD).

Pixel persistence is a minor cause of motion blur because it's only 2ms out
of a 8ms refresh (25%) at 120Hz, and only 2ms/16ms (<15%) at 60Hz.
The vast majority of motion blur you see, is caused by eye tracking on
today's LCD monitors. A lot of this is explained in Science & References.

Some TV manufacturers purchase $10,000+ tracking cameras to test motion blur.
An example pursuit camera setup: MotionMaster Motion Blur Measurement Kit.

Either way, thank you for posting your PixPerAn image. It's truly the best ever seen
for any LCD monitor. The new 1ms panels, plus LightBoost, yields CRT quality motion.

 

[Mark Rejhon]

I also did the readability test and was able to read rather easy upto level 24. At 25 it was going so fast I was only able to read the first 5 characters. I then tried the maximum of 30 and the text was still readable, however, because of the speed my head/eyes were unable to follow the text, it was still readable though.

Yes, me too. We're finally getting CRT-quality motion scores today with the BENQ XL2411T in LightBoost mode, in true motion tests. This is unprecedented for LCD!

in BF3 my scores definitly are improving. Especially in close combat circling around enemies. I'm able to keep on focus, where it used to blur all. GREAT! Also spotting foes from the corner of your eye when running, flying or driving improved a lot.

Same here too, it really helps "Scout" in Team Fortress 2. THe Quake Live players on esreality forums are really buzzing about this monitor too. (Especially big wide-open spaces, like black-sky areas, where you have to shoot faraway enemies. They're motion blurred if you turne too fast, but there's no motion blur with a LightBoost monitor)

P.S. While we're talking about BF3, can you copy-and-paste your entire post into this Battlefield 3 Forum Thread that talks about LightBoost?
http://battlelog.battlefield.com/bf3/forum/threadview/2832654625402301151/

 

[Mark Rejhon]

I now have the BENQ 20t & a 3d vision 2.0 kit but really I am unsure if it is working - how can I tell? I see the lightboost option is now enabled in the monitor's OSD though.

If you bought the 3D kit and have already been gaming with 3D stereoscopic using 3D Vision 2, you might have already had LightBoost enabled (unless your monitor said LightBoost was not enabled) -- and long had the zero motion blur effect already. So it's possible you're already used to the effect already, and see no improvement by following my instructions.

A good way to test is PixPerAn, a utility at prad.de -- see
http://www.prad.de/en/monitore/testsoftware/pixperan.html
Turning on/off LightBoost makes a major difference to the moving car.
(Warning: PixPerAn doesn't run smoothly under Windows 8)

Intentionally turn OFF LightBoost (make sure monitor OSD says LightBoost is off), test PixPerAn, then:
Intentionally turn ON LightBoost (make sure monitor OSD says LightBoost is on), test PixPerAn again.
(Another good test is the window-drag test, especially noticeable if using a gaming mouse)

Turning off LightBoost is disabling the stereoscopic checkbox in nVidia Control Panel. (Sometimes you have to enable it again, then disable again in two cycles, before it "takes").

 

[Mark Rejhon]

Well I tried this using a 580gtx and benq 2411t, and all i can say is NO THANKS! After 5 mins my head ached but I thought i might get used to it, I did a bit but the deal breaker was well I think it was input lag. I play a lot of cs source and with lightboost on the hit boxes/models were all wrong.

Question -- when you say this, is this a monitor artifact that shows up? Or is this a videogame bug with LightBoost?

Either way, LightBoost is not for everyone (some hate it due to flicker, people who disliked a CRT even at high refresh rates) but clearly, some people love it! (especially long-time former CRT gamers)

 

[Mark Rejhon]

The lack of 'noticeable' trailing in-game whilst using Light Boost is absolutely great, no doubt, and yes it's better than anything the other 120Hz LCD's can provide - but i'm not sure that you should be selling it as a feature that's for everybody, because without it...

I'm not -- I know LightBoost is not for everyone. That said, many people agree that this is an under-advertised feature.

The reason why it's still a hugely successful gaming monitor, potentially the best, is it's extremely low input lag. PCM reports that the BenQ XL2411T has it's lowest input lag whilst running in 144Hz, and you're forced to use 100 or 120 to utilize lightboost technology. I don't know of a single top competitive player that would sacrifice the lowest input lag to use such technology, even with a difference of just 2-3ms.

It depends on the type of gameplay. Close combat? Snipering? Fast scout in TF2? Sometimes the lack of motion blur gives you a bigger advantage (e.g. faster human reaction time by 100-200ms, because you could identify many tiny far-away snipers faster and shoot them faster, without stopping moving) than the input lag. Circle strafing a far-away enemy using super-fast run? Shooting multiple far-away snipers? Shooting without stopping turning first? Certain tasks LightBoost excels, and give you a massive reaction time advantage (hundreds of milliseconds faster reaction for certain tasks). However, for other tasks, the 2-3ms less input lag is more important. It's a give-or-take thing. Also, it is important that LightBoost often forces VSYNC ON, so you get unexpected input lag, it behooves upon you to make sure you've eliminated all other sources of input lag first, before making a final judgement whether LightBoost gives you a gaming advantage or not.

Some input lag tests will need to be done, because there's more to it. LightBoost sometimes tend to turn on VSYNC (because that's needed for 3D), and that's an automatic +8ms lag at 120Hz. That's not the difference between 120Hz vs 144Hz, and that's the input lag most people is currently complaining about. However, I was able to turn off VSYNC in many games while keeping LightBoost enabled

If he does buy into it and it causes him headaches

If you disliked CRT, you will dislike LightBoost. The flicker is similar, if you're not a long-time CRT gamer that likes the zero-motion-blur of CRT. In today's century, some gamers here may never used a computer CRT monitor and may not be familiar with the motion blur differences of CRT versus LCD. Either way, within a month, I'll probably have a LightBoost FAQ that covers the pros and cons -- to make sure people are educated about the pros and cons of LightBoost. The good news is LightBoost is an optional feature that can be turned on/off, and that LightBoost monitors happen to be 120Hz monitors that are better for gaming than 60Hz anyway, so the risk of buying a LightBoost monitor (untested) is lessened by the existence of the other advantages.

or he owns a system that when locking FPS introduces fluctuations in said value on games like TF2 - bringing with it an effect similar to microstuttering - then what does he do?

You can turn off VSYNC while having LightBoost, assuming you've installed the registry file to keep LightBoost persistent. LightBoost still greatly eliminates motion blur with >120fps VSYNC-OFF gaming, so you still gain.

 

[Mark Rejhon]

Here's examples improved gaming abilities, caused by the lack of motion blur during moving fast.
Competition gamers should not dismiss LightBoost quickly, because:

I can confirm this works on BENQ XL2420TX
EDIT: And OMG i can play scout so much better now in TF2, this is borderline cheating.
original post

in BF3 my scores definitly are improving. Especially in close combat circling around enemies. I'm able to keep on focus, where it used to blur all. GREAT! Also spotting foes from the corner of your eye when running, flying or driving improved a lot.

As you can see, for *certain* tasks like fast movements, the faster human reaction time (100-200ms improvement in human brain reaction time) on specific operations, can be more important than the +2-3ms added input lag that LightBoost might give you (assuming same VSYNC status you you usually use before; important to doublecheck). It totally all depends on what type of gaming you do, and what gaming habits you have, ability to utilize old CRT-gaming skillz, and other factors.

This shows, sometimes 2-3ms input lag is definitely more important, but it's NOT unamiously 100% more important 100% all the time when a certain fast-reaction task is hobbled by motion blur. Remember, lag can include human brain reaction time!
...So it depends on the game, the operation, the person(gamer), the habits, the server being in sync with clients, etc.

Although the best zero motion blur effect occurs at "FPS=Hz"; I should stress that LightBoost still benefits VSYNC-OFF "FPS higher than Hz" gaming too, just like "FPS higher than Hz" gaming still worked great with competition gamers on CRT's. (Note: I've heard it's very difficult to turn off VSYNC with LightBoost enabled, so I'll try to hunt down a new set of instructions for this; keep tuned) The motion characteristics is the same as good impulse-driven displays such as CRT of the same refresh rate (CRT 120Hz).

The main problem is the user experience (you have to go through a lot of steps to get LightBoost working in 2D mode, even for vendor-supported instructions). LightBoost was invented primarily for 3D, to strobe the backlight only when 3D shutter glasses are open (It reduces crosstalk between eyes, and it brightens the image through dark 3D shutter glasses). What we need is an easier way to turn on a strobe backlight feature easily, with minimum interference with input lag. (And ideally LightBoost ability at 144Hz, too.)

Bottom line:
While LightBoost does not benefit everyone, it is an excellent and very unadvertised optional feature in otherwise good videogaming LCD monitors. You can still turn the feature on or off.

 

[Mark Rejhon]

but i think what you're missing is the feature that everyone wants from CRT monitors before zero motion blur, 0ms input lag, and i fail to see how the two are related. I love this effect, but in my opinion you have the priorities in the wrong order.

To the contrary -- we are both right for different reasons. I understand where you're coming from, but remember that the priorities depends on many variables -- as I've already said (e.g. game, game play style, person, game operation, etc.) Even you can agree that different people play video games in very different ways. Some people never circle strafe, others do. (to give one example). The advantage of certain gameplay tactics may be a "few ms" faster brain response, a different may have "a lot of ms" faster response with no blur, other gameplay may make no hoot of a difference and depend more on input lag. Remember, gameplay reaction time is the whole chain including the human brain too.

In certain situations where we can't have a CRT (e.g. unavailability of a FW900, or can't lug it with you to a LAN party), the question is what an individual may give up in "X" ms lag in order to get less motion blur. Is it worth giving up 0.1ms? 0.5ms? 1ms? 2ms? 10ms? Maybe you set to a lower threshold, while I set to a higher threshold. There is really no fixed "one size fits all" tradeoff. We can all disagree what the cutoff point is where the zero motion blur effect is no longer worth it.

....that said, we can't deny that it's apparently helping *SOME* people's gaming abilities. So there is at least /some/ sense into what I'm trying to say here (replace the numbers I've quoted with your own numbers that you think is more accurate, the spirit remains the same)

The real question is how it averages out (Example: does quicker reaction time due to zero motion blur happen often enough & outweigh the slight added input lag, for a specific person for a specific game, on a specific computer configuration? etc)

Each to their own, keep up the good work with spreading this tweak.

Thanks. It's certainly an under-advertised feature!

 

[Mark Rejhon]

I fear the strobe might have some longer term exposure issues also. I walked away from a BF3 game the other night and had huge green patches in my vision.

Have you had problems with CRT videogaming back in the day; and have had sore eyes from gaming for long periods on CRT? I'm finding that I'm seeing no difference in eyestrain for me, but then again, I was never bothered by CRT at high refresh rates (at least 85Hz). LightBoost is not for everyone, as it does bring certain disadvantages. A possible solution is a higher-strobe-rate (higher refresh rate), such as 144Hz or even 180Hz or 240Hz (though that would require a lot of GPU!)

I have noticed the lighting levels are a bit off with lightboost actually; in particular the lighting becomes more uneven. Below are some pics from a backlight bleed test on my new screen (if anybody has any comments on the level of bleed, go ahead, I don't know what I'm doing).

Interesting observation -- could interaction with the LCD inversion, interaction with the LCD refresh pattern, or uneveness in LED illumination during short strobes. I should test the Asus VG278H (which I have too), to see if the same thing happens on it.

 

[Mark Rejhon]

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.

 

[Mark Rejhon]

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)

 

[Mark Rejhon]

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