sharknice wrote:People are reporting TN version also has a lot of crosstalk.
It is much better if you cap your framerate -- consistent framerates tend to have much less crosstalk / multiimage effects. It's hard to distinguish crosstalk from multi-image effects (double strobing) as both of them can layer-up and combine, as I've explained in this post.
I have the VA version of the TUF monitor sitting here.
It chooses a very interesting tradeoff-formula between flicker and crosstalk. Basically, the monitor allows itself to automatically decouple flickerrate from framerrate when framerate suddenly changes too fast. The stroberate syncs up better if the framerate fluctuations are slow and you've got plenty of headroom below max-Hz and above min-Hz. Useful low-crosstalk strobe range appears to be roughly ~80Hz thru ~120Hz, so try to corrall your min-max frametime within that range. Any frametime longer than 1/80sec and shorter than 1/120sec will get amplified "crosstalk" or "double images", but the beauty is that it's easy to cap a VRR with RTSS, so you gain some extremely low-lag strobing.
It flickers at LOT LESS than the ULMB+GSYNC hack, so that's a big good benefit.
ELMB SYNC automatically starts double strobing at below roughly 80fps, and automatically starts triple-strobing below roughly ~30fps, and quadruple strobing below roughly ~20fps; it aggressively tries to avoid visible flicker, automatically preferring to add "crosstalk" instead of add annoying flicker -- you can't have it both ways. The anti-flicker algorithm is a double-edged sword, but it was the achille's heel of the combined ULMB+GSYNC hack.
So ELMB-SYNC is a good low-latency strobing mode, by simply using capped VRR with it,
and capping to a known low-crosstalk framerate. And we all know capped VRR is lower lag than flat-out max-framerate uncapped VRR (with VSYNC ON latency). You get framerate=Hz with less lag than VSYNC ON, in a way that is quite easy to do with many games. But use RTSS, since you want ultra-accurate capping, some games have inaccurate in-game capping algorithms.
Now, I think in future ELMB-SYNC monitors, there should be an adjustment of the tradeoff formula between flicker visibility versus double-image visibility.
More about crosstalk (GtG limitations) versus double images (multi-strobing a frame), which is simultaneously happening (at the same time) with wildly fluctuating frame rates on ELMB SYNC -- in
this post.
Two different things with different causes...
There's an important
distinction between strobe crosstalk and duplicate images.
The Double Image Phenomenon
All impulsed displays CRTs, plasmas, strobed LCDs -- anything that uses pulsing, flicker, strobing, flashing, phosphor, etc -- will be prone to this.
How To Fix: Use frame rate matching refresh rate, even if you have to lower your refresh rate, upgrade GPU, switch from console to PC, and/or reduce detail level, in order to achieve this.
The Strobe Crosstalk Phenomenon
This occurs when pixel transitions (GtG) is incomplete between strobe flashes. LCDs takes time to refresh pixels. For zero strobe crosstalk, GtG needs to be completed in the black interval (backlight turned off) before the screen is flashed again. Check
High Speed Videos Of LCD Refreshing to see how a non-strobed LCD refreshes. Observe how the GtG fade zone can interfere with the ability to strobe the LCD. For more information see
Strobe Crosstalk FAQ.
How To Fix: Get the fastest LCD you can get, TN panel technology, with the best strobe-tuning (e.g. NVIDIA ULMB), and use a slightly lower refresh rate to make sure that there is enough refreshtime for GtG to complete in the blanking interval between refresh cycles. And obviously, make sure framerate = refreshrate too, to avoid the other double-image phenomenon too.
The best strobe backlight LCDs will be closer to 1%-3% (e.g. NVIDIA LightBoost default setting, or NVIDIA ULMB with intentional digital contrast-range reduction) and the worst strobe backlight LCDs will be closer to almost 25% (e.g. poorly tuned VA LCDs)
Can Both Of The Two Causes Combine?
Unfortunately, yes.
Doing both at the same time (half frame rate on a strobed LCD display) such as 60fps at 120Hz on ULMB will create 3 images:
- The usual universal double image phenomenon
- Followed by a faint strobe crosstalk copy
TL;DR: Strive for framerate=Hz on impulsed displays. And strive for one of the better brands of strobing (and on a TN LCD) if you want strobing.
Blur Busters Provided Instructions:
To minimize ELMB SYNC crosstalk
PURPOSE: Avoids the double-strobe below min single-strobe Hz, and avoids amplified crosstalk near max Hz.
(1) If you haven't bought one yet, and hate crosstalk, then get the TN version of ELMB SYNC to get widest usable strobe range;
(2) Tweak your game to rarely do a longer than ~1/80sec frametime.
(3) Install RTSS and cap your framerate significantly below max Hz.
For the 155Hz TN version use a 120fps-125fps cap. For the IPS version, use a ~100-110fps cap. For the VA version, darker games may require a really low framerate cap (VA ghosting in grays). TestUFO is not a good way to test ELMB SYNC because it only tests max-Hz, and browsers are not VRR-compatible yet. The capping threshold will vary on personal preference, but as a general rule of thumb -- you want at least ~20% hertzroom below max Hz.
Mostly crosstalk-free VRR range is roughly 80Hz-120Hz(ish), assuming the framerate remains steady. Anytime a framerate suddenly changes, it takes time for the strobe to re-sync, because the strobe prioritize anti-flicker above all else.
The less time you have between refresh cycles, the less time for pixel response to finish settling the pixels (crosstalk). That's why strobing at a Hz below max Hz is better strobe quality. This is the same reason why NVIDIA added an artificial arbitrary limitation of 120Hz ULMB for 144Hz GSYNC monitors -- they could have done 144Hz ULMB easily if they were willing to withstand strobe crosstalk complaints -- so they just limited to 120Hz to make to keep crosstalk complaints to a minimum.
I'll be writing a small article about these instructions in the near future to guide ELMB-SYNC users.