HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

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HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Chief Blur Buster » 16 Oct 2022, 16:52

Full Panel Zero Crosstalk: Top/Center/Bottom Equally Clear:
No Visible Double Images with Strobing!

Hello! New HOWTO for ViewSonic XG2431 users.
Most of you already know about www.blurbusters.com/xg2431
However, there's a big update that improves strobe quality even more!

(Not applicable to any other model, not compatible with ViewSonic XG270).
These modes are even superior to previous TN panels (e.g. XL2411P), and the XG2431 supports single-strobe 60Hz.

Image

New Crosstalk-Free DIY QFT Modes For Emulator Users / 60fps Users / Low-Framerates

jbltecnicspro from HardForum provided some excellent crosstalk-free QFT 60Hz and 85Hz modes, thanks to the new ToastyX Vertical Total Calculator in the latest version. First, upgrade your ToastX CRU to at least verison 1.5.2 or later, and also download Strobe Utility from www.blurbusters.com/xg2431

Make sure to break in your panel and warm up your panel first, as cold LCDs have slower pixel response. A minor panel lottery variance may require you to re-tune overdrive gain but Vertical Total, Pulse Width and Pulse Phase is portable to all XG2431's as long as they're kept together.

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Easier Introduction to Creating Low-Crosstalk QFT Modes

Quick Frame Transport (QFT) transmits refresh cycles in 1/240sec (over the HDMI/DP cable) and the LCD will scan-out the refresh cycle in 1/240sec, even though you're only using a low refresh rate. There are two benefits to QFT -- it reduces strobe crosstalk AND simultaneously it reduces the input lag of strobing for low refresh rates.

These are excellent modes for emulators and low-framerate games (e.g. Cyberpunk 2077), especially when combined with VSYNC ON + NULL, or combined with RTSS Scanline Sync -- for ultra fluid CRT-quality motion, when motion clarity is your maximum priority above all else (colors, brightness, etc).

One of Blur Busters' problems with strobe tuning is that there are over a billion adjustment combinations for tuning XG2431 (refresh rate, quick frame transport, vertical total, pulse width, pulse phase, overdrive gain), each with subtly different crosstalk.

Thus, it can be very challenging to find the perfect combinations, harder than 100-zone CRT convergence.... until now. ViewSonic nicely allowed end-user strobe tuning, which meant thousands of users could experiment with better strobe settings -- and software vendors such as ToastyX could assist.

A new version of ToastyX has a QFT calculator that makes this much easier. Here are presets that were finally recently discovered, that no manufacturer has succeeded (DIY FTW!)

Some people have been saying these custom modes are better than a CRT tube (except for contrast ratio and color gamut).

(A) Installing Software For Creating QFT Strobe Settings
(B) Setting Things Up First
  1. Launch ToastyX CRU. We will modify copies of the existing 240 Hz EDID to create new QFT modes.
  2. Click "Detailed Resolution" and Click "Add..." button.
    Image
  3. Set refresh rate to 240 Hz to match screenshot.
    Image
  4. Select "Vertical Total Calculator".
  5. Choose your preferred refresh rate. You can create any refresh rate, but we'll provide easy examples here. up to the number of Detailed Resolution slots that the EDID spec (ToastyX) gives you.
  6. Make sure FreeSync and G-SYNC is turned off, to allow PureXP to work
60Hz QFT Mode for XG2431 (Crosstalk-Free Low-Lag Strobing)
  • Follow "Setting Up" steps 1-6
  • Then then edit the "240" to "60"
    Image
  • Then restart GPU drivers by rebooting your PC or run "restart64.exe" included with ToastyX CRU.
  • Then switch your XG2431 to 60Hz (via Control Panel, or via respective NVIDIA/AMD/Intel utility)
  • Then launch Strobe Utility, select "Pure XP Custom" and configure these settings:
    Image
IMPORTANT: Always warm up and break in your panel first! Also, you may need to readjust Overdrive Gain slightly for your specific panel (temperature, panel variances, break-in period). You might need to go about 1,2 or 3 clicks higher/lower on different panel specimens. Readjust OD Gain again occasionally if you start seeing crosstalk faintly appear again due to panel temperature (including from seasonal changes) / breakin / aging behaviors. Sub-millisecond changes to LCD GtG pixel response can make strobe crosstalk reappear.


85Hz QFT Mode for XG2431 (Crosstalk-Free Low-Lag Strobing)
  • Follow "Setting Up" steps 1-6 (again, if you created the 60Hz mode first)
  • Then then edit the "240" to "85"
    Image
  • Then restart GPU drivers by rebooting your PC or run "restart64.exe" included with ToastyX CRU.
  • Then switch your XG2431 to 85Hz (via Control Panel, or via respective NVIDIA/AMD/Intel utility)
  • Then launch Strobe Utility, select "Pure XP Custom" and configure these settings:
    Image
IMPORTANT: Always warm up and break in your panel first! Also, you may need to readjust Overdrive Gain slightly for your specific panel (temperature, panel variances, break-in period). You might need to go about 1,2 or 3 clicks higher/lower on different panel specimens. Readjust OD Gain again occasionally if you start seeing crosstalk faintly appear again due to panel temperature (including from seasonal changes) / breakin / aging behaviors. Sub-millisecond changes to LCD GtG pixel response can make strobe crosstalk reappear.

NOTE: You will have to manually change Strobe Utility settings every time you switch between strobed QFT modes such as switching between these 60Hz and 85Hz modes. Future versions of Strobe Utility is planned to memorize multiple PureXP Custom settings, to make this process easier.

Purpose Of Perfect Zero Double-Images With PureXP Custom

These instructions are for people who want to use low refresh rates on the XG2431 to more easily allow framerate=Hz strobing.

When your content is low frame rate (video playback, emulators, RTX raytraced games, etc) or if you want to completely eliminate strobe croststalk, you can get a very good CRT motion clarity feel with the ViewSonic XG2431 when all strobe crosstalk is completely eliminated.

This is not for CS:GO esports. This is for lower-framerate content where you want to lower your Hz to match refresh rate to improve motion quality:

With properly tuned QFT PureXP Custom, with properly adjusted games, combined with framerate=Hz, you concurrently get:
- Zero stutters
- Zero jitters
- Zero motion blur
- Zero crosstalk
- No double images of any kind
- Lower latency than default low Hz modes

This can produce a motion nirvana effect in some fast-motion games -- such as SEGA Sonic Hedgehog or fast-sports videos (e.g. Red Bull air races) or other fast-panning fast-scrolling content similar to www.testufo.com/map -- the immersive butter-smooth CRT effect is most amplified when all strobe crosstalk is completely eliminated.

Some people use 120Hz or 180Hz QFT as an esports compromise for RTS games (DOTA2, LOL, etc), it's lower latency than default 120Hz and 180Hz when you use RTSS Scanline Sync as the sync technology (tearingless VSYNC OFF). There will be a slight amount of crosstalk at higher refresh rates (but less crosstalk than the same refresh rate as non-QFT), that progressively gets worse the closer you get to 240, so you have to choose your sweet-spot comproimse. The zero crosstalk modes are generally from 59Hz through approximately ~100-120Hz, dependent on panel

Once enabled, you can use these QFT modes only when you switch to a lower refresh rate, and use normal 240Hz VSYNC OFF for your esports games, if you wish. Remember: Right Tool For The Right Job!

Optional Technical Reading For Fun Background Information
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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Kyouki » 17 Oct 2022, 02:09

Thank you for this write up. Gonna test this on my AW2521H unit, 240hz ULMB.
Posting details about my findings later on.
CPU: AMD R7 5800x3D ~ PBO2Tuner -30 ~ no C states
RAM: Gskill Bdie 2x16gb TridentZ Neo ~ CL16-16-16-36 1T ~ fine tuned latency
GPU: ASUS TUF 3080 10G OC Edition(v1/non-LHR) ~ disabled Pstates ~ max oced
OS: Fine tuned Windows 10 Pro, manual tuned.
Monitor: Alienware AW2521H ~ mix of ULMB/Gsync @ 240hz/360hz
More specs: https://kit.co/Kyouki/the-pc-that-stomps-you

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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Chief Blur Buster » 17 Oct 2022, 04:59

Kyouki wrote:
17 Oct 2022, 02:09
Thank you for this write up. Gonna test this on my AW2521H unit, 240hz ULMB.
Posting details about my findings later on.
NVIDIA ULMB is not directly compatible with QFT, though you can derive the other lower-Hz ULMB resolutions based off the max-Hz ULMB pixel clock -- that's a different HOWTO. What you want to do is set the maximum-Hz ULMB mode, and derive lower-Hz ULMB modes by keeping Pixel Clock and Horizontal Scan Rate (of the working ULMB mode) unchanged, to create your new ULMB low-Hz mode (e.g. ULMB 60Hz). It's an undocumented ULMB hack to create undocumented ULMB refresh rates, but does not help crosstalk much as it has unadjustable Strobe Phase, and unadjustable Overdrive Gain.

QFT can be useful for other monitors even outside of a strobing context -- it works on LG OLED HDTVs (reduces 60Hz OLED lag with 120Hz QFT, although BFI doesn't seem to wkrk).

Large VTs also reduce crosstalk on BenQ 1080p displays (DyAc, DyAc+), although not down to as low as 60Hz. XL2720Z was the first display discovered to improve with large Vertical Totals (VT1350, VT1500), but it takes ultra-large Vertical Totals to completely eliminate strobe crosstalk.

Eliminating strobe crosstalk with ordinary stock OD Gain adjustment on scaler/TCON so requires a panel with fast scanout (240Hz+) and running them with extreme refresh rate headroom (3x-4x). Some strobe backlights like LightBoost uses advanced overdrive gain that increases along the Y axis of the panel, but is not mandatory when you have lots of refresh rate headroom on a sufficiently fast panel.

However,
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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Discorz » 17 Oct 2022, 05:20

Kyouki wrote:
17 Oct 2022, 02:09
Gonna test this on my AW2521H unit, 240hz ULMB.
ULMB is already utilizing QFT at 240 and 144 Hz.
https://i.ibb.co/fxgyhP5/AW2521-H-ULMB- ... st-UFO.jpg
Compare UFOs | Do you use Blur Reduction? | Smooth Frog | Latency Split Test
Alienware AW2521H, Gigabyte M32Q, Asus VG279QM, Alienware AW2518HF, AOC C24G1, AOC G2790PX, Setup

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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Kyouki » 17 Oct 2022, 06:09

Thank you guys - was kind of hoping to get a confirmation from either of you -- else i'd test myself to see what's up despite still learning all the ropes...

Thought I was having a sub-optimal setup (well ULMB is, already by itself... limited)
Having a pretty good experience with 20-25% ULMB pulse width @ 240hz though. ^_^
CPU: AMD R7 5800x3D ~ PBO2Tuner -30 ~ no C states
RAM: Gskill Bdie 2x16gb TridentZ Neo ~ CL16-16-16-36 1T ~ fine tuned latency
GPU: ASUS TUF 3080 10G OC Edition(v1/non-LHR) ~ disabled Pstates ~ max oced
OS: Fine tuned Windows 10 Pro, manual tuned.
Monitor: Alienware AW2521H ~ mix of ULMB/Gsync @ 240hz/360hz
More specs: https://kit.co/Kyouki/the-pc-that-stomps-you

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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Chief Blur Buster » 17 Oct 2022, 07:48

Discorz wrote:
17 Oct 2022, 05:20
Kyouki wrote:
17 Oct 2022, 02:09
Gonna test this on my AW2521H unit, 240hz ULMB.
ULMB is already utilizing QFT at 240 and 144 Hz.
https://i.ibb.co/fxgyhP5/AW2521-H-ULMB- ... st-UFO.jpg
QFT is not a pursuit camera image. QFT is at the signal layer (aka faster pixel transmission on the cable).
Can you please post a screenshot of the video signal timings (e.g. screenshot of ToastyX).

Please post ToastyX proof that ULMB is now finally using QFT.
It does use internal scan conversion, but in the past it has not used signal-based QFT.

If a 360Hz monitor is using QFT for 240Hz strobe, then its vertical total would be approximately 1125 * (360/240) = approx VT1680+ ... But I don't think ULMB is using large vertical totals transmitted from the GPU-side, but historically instead utilizes internal scan conversion instead as the crosstalk-reduction method. Though NVIDA is known to tinker, I haven't seen large vertical totals built into the monitor's EDID -- because QFT would be a custom non-VESA EDID...
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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Discorz » 17 Oct 2022, 09:56

Chief Blur Buster wrote:
17 Oct 2022, 07:48
But I don't think ULMB is using large vertical totals transmitted from the GPU-side, but historically instead utilizes internal scan conversion instead as the crosstalk-reduction method.
I assumed its QFT as 144 and 240 Hz had less crosstalk than average high refresh rate display. I don't have nvidia gpu anymore to check timings (ULMB is not supported on AMD cards), but I have saved 60Hz ULMB timings derived from 144Hz which seems to be exactly same as ones you posted here.
Compare UFOs | Do you use Blur Reduction? | Smooth Frog | Latency Split Test
Alienware AW2521H, Gigabyte M32Q, Asus VG279QM, Alienware AW2518HF, AOC C24G1, AOC G2790PX, Setup

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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by michaelcycle00 » 17 Oct 2022, 16:59

Chief, when are we gonna get a tutorial about QFT modes for the XL2566K (BenQ 360hz)? And how low do you reckon we could go with it? I'm guessing as low as 100hz but I don't know, I'd be satisfied with 120hz.

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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Chief Blur Buster » 17 Oct 2022, 22:51

michaelcycle00 wrote:
17 Oct 2022, 16:59
Chief, when are we gonna get a tutorial about QFT modes for the XL2566K (BenQ 360hz)? And how low do you reckon we could go with it? I'm guessing as low as 100hz but I don't know, I'd be satisfied with 120hz.
A generic QFT HOWTO is being created for the main Blur Busters website soon.

Usually you're simply using the new Vertical Total Calculator (QFT) in the new version of ToastyX. If you are already familiar with ToastyX, you just you load the max-Hz resolution, make sure it's already working, THEN you select "Vertical Total Calculator" and THEN edit the refresh rate directly.

For ToastyX CRU veterans, it's really now just a 3-step procedure. Voila! ToastyX does the rest automatically, no need for manual calculations anymore, no trial-and-error, it just automagically computes a working VT.

For ToastyX CRU newbies, it's harder though.
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Re: HOWTO: Settings For Full Panel Crosstalk-Free Low-Lag Strobing (ViewSonic XG2431)

Post by Chief Blur Buster » 17 Oct 2022, 22:57

Discorz wrote:
17 Oct 2022, 09:56
Chief Blur Buster wrote:
17 Oct 2022, 07:48
But I don't think ULMB is using large vertical totals transmitted from the GPU-side, but historically instead utilizes internal scan conversion instead as the crosstalk-reduction method.
I assumed its QFT as 144 and 240 Hz had less crosstalk than average high refresh rate display. I don't have nvidia gpu anymore to check timings (ULMB is not supported on AMD cards), but I have saved 60Hz ULMB timings derived from 144Hz which seems to be exactly same as ones you posted here.
Unfortunately, none of us can assume QFT by pursuit camera:y
- You can still get low crosstalk without QFT (if pixel response is fast enough to hide in the small VBI)
- You can still get crosstalk with QFT (if Hz is high or pixel response is slow enough in milliseconds to exceed VBI in milliseconds)
- I've seen panels have less crosstalk without QFT (if fast enough pixel response) than a different panel with QFT (if slow enough pixel response)

But this is true:
- Assuming the SAME panel of SAME model of SAME pixel response of SAME pulse width brightness of SAME Hz, you can get less crosstalk with QFT than without QFT. That's key. Enabling QFT on the same said panel reduces crosstalk relative to itself without QFT.

Different panels are apples vs bananas -- their strobing algorithms and implementations are so different that the addition/removal of QFT may not cause a leapfrog effect.

Also, you can use internal scan conversion instead of QFT to reduce crosstalk. All LightBoost and ULMB panels generally do the internal scan conversion technique instead of QFT (including recent versions of ULMB AFAIK), so if you do 144Hz ULMB on a 240Hz monitor, it's always transmitting first-thru-last-pixel over a period of 1/144sec on the panel, even if the panel buffers the 144Hz signal and scans-out in 1/240sec. The problem is scan conversion requires buffering, which adds more lag than QFT-based strobing.

NVIDIA has historically never used signal-level QFT on the video cable. However, QFT will improve ULMB over whatever the pursuit camera captured for non-QFT, especially if there's a strobe-phase and a pulse-width adjustment. ULMB has a PW adjustment, but generally no PP adjustment.

So ULMB will improve, but will not improve nearly as much as an XG2431 with QFT + large Hz headroom + large VT + PW + PP + OD all adjusted optimally, because ULMB doesn't allow you to readjust all those variables. I don't there's any monitor (yet) other than XG2431 with such a wide-adjustment-range of a larger number of strobe-affecting settings. No ULMB implementation of NVIDIA's I've seen yet gets as clear as an optimally-adjusted XG2431 at ~100Hz

So since XG2431 is one of the first desktop IPS computer monitors to go fully crosstalk-free Top/Center/Bottom strobing, I haven't yet seen NVIDIA ULMB (not even QFT-ULMB) match that quality after a very good, surgical, manual calibration -- partially because of ULMB's non-adjustable OD Gain, and ULMB's non-adjustable Pulse Phase. You need control of maximum number of strobe variables to whac-a-mole ever-more percentage of strobe crosstalk to oblivion.

That being said, ULMB+QFT is possible with some hacks (custom Hz strobe is already defacto QFT based off the max strobe Hz). So you can only QFT 1/240sec on a 360Hz ULMB monitor, and you won't be able to adjust the pulse phase -- so you may still have, say, bottom-edge crosstalk even if you completely eliminate top-edge crosstalk. Ouch.

Most people are not familiar with the refresh rate headroom necessary to even almost eliminate strobe crosstalk.

Hope this makes sense!
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