Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Ask about motion blur reduction in gaming monitors. Includes ULMB (Ultra Low Motion Blur), NVIDIA LightBoost, ASUS ELMB, BenQ/Zowie DyAc, Turbo240, ToastyX Strobelight, etc.
Burgz
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Joined: 21 Mar 2020, 17:41

Re: Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Post by Burgz » 28 Mar 2020, 02:46

Chief Blur Buster wrote:
27 Mar 2020, 20:19
HyperSlayer72 wrote:
27 Mar 2020, 20:00
I was also asking about pwm/dc when not using blur reduction backlights. Just normal display modes. I remember reading a thread that said pwm monitors natively have less blur than flicker free panels. It advised to stick with high hz pwm even if you planned on not using strobbing. Based on these beliefs idea it begs the question, why did the industry stop using pwm all together for high hz monitors. I understand making flicker free monitors for those with eyestrain concerns. But for many other buyers myself included i'd gladly take clearer motion over a "no eyestrain" feature.
All strobe backlights, are automatically a PWM mode.
(A good kind of PWM)

PWM-free monitors still re-enable (a better kind of) PWM for motion blur reduction.

BFI is PWM.
Strobe is PWM.
ULMB is PWM.
LightBoost is PWM.
Aim Stabilizer is PWM
PureXP+ is PWM
DyAc is PWM

PWM stands for Pulse Width Modulation. Flashing a backlight on and off. A strobe backlight is also flashing. Except it's properly synchronized to the refresh rate.

It's only PWM-free in non-strobed mode. There is less motion blur with PWM because PWM dimming provides "accidental blur reduction" benefits. Unfortunately, other people get more pain from PWM dimming than from blur reduction benefits.

Open up a monitor menu on a GSYNC monitor that includes ULMB, and you'll see "ULMB Pulse Width", so you can adjust the size of the pulse to improve your MPRT. LightBoost 10% vs 100% is a Pulse Width Adjustment! So if you were a user of LightBoost 10%, you simply adjusted your LightBoost PWM setting.

These settings adjust the size of the pulse width in PWM:
  • NVIDIA "LIghtBoost" % setting
  • NVIDIA "ULMB Pulse Width" setting
  • BenQ "Strobe Duty" setting
  • ViewSonic "PureXP+ Levels" (Light|Normal|Extreme|Ultra)
  • Acer "VRB" Normal/Extreme
The industry simply moved to PWM-free for non-strobed modes, and healthy one-pulse-per-refresh PWM for strobed modes.

(They just don't market strobe as PWM. But strobe is same thing as PWM).

The industry never stopped using PWM
Because PWM is still mandatory for motion blur reduction -- at least until we can do strobeless blur reduction via ultrahigh refresh rates instead. They just switched from nasty multi-strobe PWM to good single-strobe PWM.

Image
  • PWM dimming uses top rows (360Hz or 480Hz PWM on a 120Hz monitor produces that)
  • PWM blur reduction uses bottom row (beautiful single pulse PWM during fps=Hz).
Strobing is PWM. PWM is stobing. It's the same thing, artifacts-wise. Whether be PWM dimming (120fps at 360Hz PWM dimming) or multi-strobing (e.g. 60fps at 120Hz LightBoost). Except blur reduction strobing is simply strobing synchronized to refresh rate. Or PWM synchronized to refresh rate. It's also why you want fps=Hz to sync your strobe rate to the frame rate, to maximize motion pleasure and minimize eyestrain from artifacts (such as duplicate images).

Marketing simply changed.

Good PWM is now labelled "motion blur reduction" by it various brand names (LightBoost, ULMB, DyAc, ELMB, PureXP, etc). So you see, a PWM-free monitor with motion blur reduction mode, STILL has PWM. Just PWM made optional.

Also, please re-read my previous reply. ;)
Tyvm for this it helps a lot. Is there a blur reduction for xg2401? Purexp? I can't seem to find anything ( I guess it doesn't matter since I have an xn252q coming tomorrow :D)

It does have an option to reduce blur with a mode in the OSD called 'low input lag' or 'Response time' setting I forget which one - if I have it set to advanced it's kinda blurry in games (not using any vrr tho - uncapped fps until new 240hz arrives) - if I put it to ultra fast I get ghosting, but it certainly makes character models more prominent. Does this affect input lag negatively or positively in any way? Also with overdrive I should probably be using vrr for less ghosting?

Ah shit I just asked 100 dumb questions because I'm very new to all this - don't worry you don't have to answer as I say new monitor tomorrow..

Estrada00
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Joined: 07 Jul 2019, 14:03

Re: Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Post by Estrada00 » 28 Mar 2020, 08:00

I really having fun time reading chief's responses although my understanding of it remain low. I will try to understand it eventually over time.
I will be interested hearing back from you , Burgz , after you get your XN253Q(XF252Q gsync variant) set to 144hz/120hz strobing, normal OD and compare it to XG2401 in terms of input lag and motion blur
XG2401 ,XG2402,XG240r(which i have ) and Omen x 25f dont have blur reduction mode...iirc still low input lag monitors and good motion blur if i keep it fps=hz without frame fluctuations.

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Re: Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Post by Chief Blur Buster » 28 Mar 2020, 15:06

HyperSlayer72 wrote:
27 Mar 2020, 20:53
Regarding the Asus VG279QM what do you think of the 280hz strobbed photo tftcentral provided.
It looks correct for what 240Hz strobing looks like on all of the 240Hz IPS. The really beautiful crosstalk-free IPS strobing only occurs at lower refresh rates (e.g. 100Hz, 120Hz).

Some vendors lock the strobe Hz intentionally to avoid poor-quality strobing. In theory, it is only a 1 line code change (if NVIDIA wishes) to enable 240Hz strobing at 240Hz on NVIDIA ULMB monitors. But NVIDIA limits ULMB strobe to 144Hz, to avoid complaints on strobe crosstalk at 240Hz. While other vendors unlock the limit, letting users decide between crosstalk-vs-Hz tradeoff. Any refresh rate can be strobed, except LIghtBoost limits it to 100Hz and 120Hz. While ULMB limits it to 3 or 4 refresh rates. While some other vendors allow any-Hz strobing. And varying levels of flexibilities between all the vendors.
HyperSlayer72 wrote:
27 Mar 2020, 20:53
It looks less like there is strobe crosstalk and more to me like the camera the photo was taken with doesn't have a fast enough shutter. If that's really how it looks in person that's a bit of a shame.
Actually, that is a pursuit image (confirmed), and that is strobe crosstalk (confirmed). At 240Hz, the crosstalk step is half distance at 120Hz. See section "Duplicate Images During BFI = (Hz Divided by Frame Rate)" halfway down www.blurbusters.com/1000hz-journey for strobe-crosstalk-separation mathematics.

Strobe crosstalk on all 240Hz monitors is worse at 240Hz than your LightBoost on your VG248QE. But you're at least looking at a fairly big upgrade if you use refresh rate headroom (and if your monitor model correctly uses the refresh rate headroom to reduce crosstalk at lower refresh rates)

Another great article is The Stroboscopic Effect of Finite Frame Rate Displays.

-- Quality Priority (low crosstalk) If you want low-crosstalk strobing, you will have to use refresh rate headroom to avoid the strobe crosstalk (e.g. 180Hz strobe on 240Hz BenQ TN, or 120Hz strobe on 240Hz ViewSonic XG270, etc).
-- Latency Priority If you don't care about crosstalk and prefer lowest lag, 240fps at 240Hz DyAc will be almost as lagless as 240Hz non-DyAc (average 2ms latency penalty -- 0ms for some parts of the screen, depending on where you intentionally calibrate the crosstalk bar to)

Thanks to the nature of strobing -- ignoring crosstalk -- 1ms MPRT motion looks identical all refresh rates, since motion blur is the strobe flash length, not the refresh cycle length (as it is for non-strobed). That said, if crosstalk visibility is the same, and your GPU can keep up, higher Hz still have less stroboscopic effects (phantom array effects), so there is still benefit to going higher Hz. But the improvements of raising refresh rates during strobing is not nearly as dramatic (blur-wise) as raising refresh rates during non-strobed (nonstrobed 240Hz has half the motion blur of nonstrobed 120Hz)
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Re: Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Post by Chief Blur Buster » 28 Mar 2020, 15:07

Estrada00 wrote:
28 Mar 2020, 08:00
I really having fun time reading chief's responses although my understanding of it remain low. I will try to understand it eventually over time.
You're welcome
Burgz wrote:
28 Mar 2020, 02:46
Tyvm for this it helps a lot.
You're welcome.
Burgz wrote:
28 Mar 2020, 02:46
Is there a blur reduction for xg2401?
No for the XG2401 or XG2402.

Response time is simply overdrive setting.
Head of Blur Busters - BlurBusters.com | TestUFO.com | Follow @BlurBusters on Twitter

       To support Blur Busters:
       • Official List of Best Gaming Monitors
       • List of G-SYNC Monitors
       • List of FreeSync Monitors
       • List of Ultrawide Monitors

alexander1986
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Joined: 10 Jan 2019, 01:07

Re: Could someone "school" me on motion blur by chance? Also Requesting <240hz Strobbed Photos.

Post by alexander1986 » 29 Mar 2020, 03:01

Burgz wrote:
28 Mar 2020, 02:46

Tyvm for this it helps a lot. Is there a blur reduction for xg2401? Purexp? I can't seem to find anything ( I guess it doesn't matter since I have an xn252q coming tomorrow :D)

It does have an option to reduce blur with a mode in the OSD called 'low input lag' or 'Response time' setting I forget which one - if I have it set to advanced it's kinda blurry in games (not using any vrr tho - uncapped fps until new 240hz arrives) - if I put it to ultra fast I get ghosting, but it certainly makes character models more prominent. Does this affect input lag negatively or positively in any way? Also with overdrive I should probably be using vrr for less ghosting?

Ah shit I just asked 100 dumb questions because I'm very new to all this - don't worry you don't have to answer as I say new monitor tomorrow..

if possible give us some photos/videos of strobing and nonstrobing testufo tests when you get your acer monitor! : )

like a mini review with some pictures and videos would be awesome, always is good IMO !

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