UFO Ghosting Test changing fps with fixed hz value

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monfy
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UFO Ghosting Test changing fps with fixed hz value

Post by monfy » 27 Jun 2022, 20:25

Is it possible to change fps on the UFO Ghosting Test but keep hz fixed, or does the fps always have to match the hz for this test?

I have the LG C2 42 OLED and I want see how the test looks at around 200-400 fps while in 120hz mode.

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RealNC
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Re: UFO Ghosting Test changing fps with fixed hz value

Post by RealNC » 30 Jun 2022, 09:01

monfy wrote:
27 Jun 2022, 20:25
Is it possible to change fps on the UFO Ghosting Test but keep hz fixed, or does the fps always have to match the hz for this test?

I have the LG C2 42 OLED and I want see how the test looks at around 200-400 fps while in 120hz mode.
Can't you use the FPS test for that? Meaning: https://www.testufo.com/framerates#coun ... ne&pps=960
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monfy
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Re: UFO Ghosting Test changing fps with fixed hz value

Post by monfy » 30 Jun 2022, 13:17

RealNC wrote:
30 Jun 2022, 09:01
monfy wrote:
27 Jun 2022, 20:25
Is it possible to change fps on the UFO Ghosting Test but keep hz fixed, or does the fps always have to match the hz for this test?

I have the LG C2 42 OLED and I want see how the test looks at around 200-400 fps while in 120hz mode.
Can't you use the FPS test for that? Meaning: https://www.testufo.com/framerates#coun ... ne&pps=960
The FPS test you linked only shows FPS that is the same as your monitors refresh rate or less. I'm specifically looking for a ghosting test where I can set FPS higher than my refresh rate. So essentially a ufo ghosting test where it keeps the hz fixed but allows me to vary the FPS. Does this exist? And if not, any plans on it becoming a feature soon?

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RealNC
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Re: UFO Ghosting Test changing fps with fixed hz value

Post by RealNC » 30 Jun 2022, 13:25

monfy wrote:
30 Jun 2022, 13:17
The FPS test you linked only shows FPS that is the same as your monitors refresh rate or less. I'm specifically looking for a ghosting test where I can set FPS higher than my refresh rate. So essentially a ufo ghosting test where it keeps the hz fixed but allows me to vary the FPS. Does this exist? And if not, any plans on it becoming a feature soon?
I don't see how that's useful, so I don't think so. Doing that tells you absolutely nothing about the display you can't already tell with the other tests.
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Re: UFO Ghosting Test changing fps with fixed hz value

Post by Chief Blur Buster » 06 Jul 2022, 16:48

Sometimes the goal is testing framerate behaviors, not just the display...

Framerate behaviors can generate extra blur, when we're in refresh rate stratospheres.
70 stutters per second at 360 Hz = stutters too fast = stutter blends to extra blur = like fast vibrating music string.

Confused as ghosting, it is just persistence-blur from the widest stutter amplitude components of the stutter, but it can sometimes add/distort the ghosting. Also VRR-based frametime-based overdrive algorithms can look different at a steady low framerate, or a steady high framerate, but then looks different when you add extra stutter-derived persistence blur layered on top of it....

;) Framerate-vs-Hz mismatches can add extra motion blur via high-frequency jitter.

The stutter-to-blur continuum as seen at www.testufo.com/eyetracking#speed=-1 ... Watch the bottom UFO for 20 seconds.

The bottom line is that high frequency stutter/jitter (70 stutters per second at 240Hz) can vibrate so fast that it just looks like extra motion blur, and you can trigger that by doing certain framerates beyond Hz, to create various kinds of framerate-vs-Hz mismatch stutter, at certain frequencies that looks like blur instead of stutter.

Web browsers is VSYNC ON so it's "hard" to do framerates beyond Hz, but I found a Rube Goldberg way. I can still emulate the jitter mechanics and tearing mechanics by writing a software-based display emulator.

Basically internally emulate a raster inside TestUFO and create simulated refresh cycles every VSYNC ON frame. Then I virtualize the higher/lower framerates, to generate tearing and/or jitter mechanics.

Basically to do what the OP asks, I'd do an unseen simulated offscreen display inside TestUFO logic. And simulate a sync technology (e.g. VSYNC OFF) to it. The framebuffers would be visually identical to a refresh cycle with real VSYNC OFF, including tearing and jitter and blur. It won't simulate VSYNC OFF latency because I'm still outtputting these simulated refresh cycles via a VSYNC ON conduit, but it would capture every single visual of a VSYNC OFF display (of the same output Hz)

By doing that (virtualized framerates on a virtualized display), I can at least simulate the same jitter/tearing mechanics of a framerate above Hz, within a VSYNC ON conduit.

Virtualized displays are part of TestUFO's future (e.g. CRT electron beam simulators, e.g. using 16 digital refresh cycles to emulate 1 CRT refresh cycle, on a future 1000Hz display), and I have determined I can virtualize displays even at low Hz, for other purposes such as simulating sync technologies.

I already simulate VRR anyway at www.testufo.com/vrr and algorithmically it's easy for my mind mentally to accurately simulate VSYNC OFF, and then layer a higher-framerate-than-Hz over that virtualized display workflow, e.g. generating more TestUFO frames than Hz internally and spraying them into an internal virtualized display, before outputting these virtualized refresh cycles (as one VSYNC ON frame).

So yes, it is possible -- through a very Rube Goldberg way (internally virtualized/simulated display). Emulators already do this (simulate a raster to a virtualized 60Hz display internally) to be compatible with beam racing and raster interrupt apps, but instead I'm virtualizing VSYNC OFF (via a VSYNC ON display) to generate the artifacts of VSYNC OFF that are both spatial (tearing) and temporal (extra blur from high-frequency jitter)

Not a high priority, but the request is still somewhat sound because of the stutter-to-blur continuum, and it is known framerate-vs-Hz mismatches generates a form of microstutter, that is sometimes high frequency (blends to extra display motion blur).

I need to teach people what tearing looks like, so I want to do a better "simulated VSYNC OFF" TestUFO via internal display virtualization. This could double as the test that OP is asking for. A new TestUFO test needs multiple reasons to exist, and the OP just adds an additional (niche) one.

One idea is that I can daisychain tests to a different test. For example, run any TestUFO through a software BFI engine, or run any TestUFO through simulated VRR engine, or run any TestUFO at a custom framerate through a simulated-VSYNC OFF-display engine. Or run any TestUFO motion test through a TestUFO CRT electron beam simulator. The plan is to eventually convert TestUFO to instantiable object oriented programming to allow me to run TestUFO through another TestUFO, to do magical things like these later this decade.

Display virtualization/simulators are a big planned part of Blur Busters' future, as display virtualization has many real-world applications too (e.g. not just in teaching, training, but also things like simulating a CRT electron beam in real time via brute digital Hz, for emulator retro-look preservation purposes).

I briefly tested that I was able to use the display raster virtualization technique to successfully virtualizes VSYNC OFF (in appearance, but not latency) over a VSYNC ON conduit.
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