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Toys/Lag: Jerk Monitor

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21–30 of 63 posts

Re: Toys/Lag: Jerk Monitor

#21

I found that plugging my keyboards directly into my Mac’s limited USB ports is noticably faster. I’m curious if there is a USB hub that I could buy of higher quality as my mac doesn’t have too much i/o

‘USB hub’ and ‘quality’ never go together.

I’d love to be wrong on this but haven’t been so far.

Re: Toys/Lag: Jerk Monitor

#22
post #19

Earlier quoted context omitted.

Higher refresh rates don't have to be perceptible to be useful: they can shift the balance in head-to-head gaming. Imagine 2 identical gaming setups with 2 players that have the same skill set. In an FPS game, you'd expect each of those players to win 50% of the games. Now switch one monitor from 120Hz to 240Hz. On average, the player on the 240Hz monitor will see their adversary 4ms earlier than the player on the 12…

I think this sort of effect odd what makes people think they can tell the difference - they can notice the indirect side-effects that correlate with the difference. A pro FPS player might notice that they loose contests peeking around corners more often. Obviously network latency in online games will be a factor as well, but since it likely averages out for both players over time, I would guess you can mostly discoun…

I play video games at a decently high level (like top ~10% in a few competitive games). To support what you’re saying, I can tell the difference between 144hz and 240hz if I’m in control. For example, if I can shake the screen around.

If I’m just watching, I’m not sure I could even tell the difference between 60hz and 144hz.

Re: Toys/Lag: Jerk Monitor

#23

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were…

So tired of defending against this same, old, completely wrong intuition from people especially those saying "do the science" to justify their ignorance instead of looking themselves since the science has already been done and it's coming up on a full century old.

From this one paper alone, humans can perceive information from a single frame at 2000 Hz.

https://doi.org/10.1080/00223980.1945.9917254

Humans can read numbers and reproduce them immediately a 5 digit number is displayed for 1 frame at 400 fps. This is a single exposure, it is not a looping thing with persistence of vision or anything like that. 7 digit numbers required the framerate to be 333 fps. Another student produced 9 digit number from a single frame at 300 fps. These were the average results. The record results were a correct reproduction of a 7 digit number from a single viewing of a single frame at 2000 Hz. This was the limit within 2% accuracy of the tachistoscopic equipment in question. From the progression of the students chasing records, no slowing of their progression had ever been in sight. The later papers from this author involve considerable engineering difficulty to construct an even faster tachistocope and are limited by 1930s-1940s technology.

This research led the US Navy in WW2 to adopt tachistotopic training methods for aircraft recognition replacing the WEFT paradigm (which had approximately a 0% success rate) to a 1 frame at 75 fps paradigm which led to 95% of cadets reaching 80% accuracy on recognition, and 100% of cadets reaching 62.5% accuracy after just 50 sessions.

Yes, humans can see 2000 fps. Yes, humans can see well beyond 2000 fps in later work from this researcher.

https://doi.org/10.1080/00223980.1945.9917254

Yes, humans can detect flicker well above 1000 fps in daily life at the periphery of vision with cone cells as cone cells can fire from a single photon of light and our edge detection circuits operate at a far higher frequency than our luminance and flicker-fusion circuits. Here's flicker being discriminated from steady light at an average of 2 kHz for 40 degree saccades, and an upper limit above 5 kHz during 20 degree saccades, which would be much more typical for eyes on a computer monitor.

There is no known upper limit to the frequency of human vision that is detectable. As far as I know, all studies (such as this one I link) have always been able to measure up to the reliable detection limit of their equipment, never up to a human limit.

Re: Toys/Lag: Jerk Monitor

#24
post #11

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were…

As per the post, I wrote this tool to confirm I was getting jerks of ~10ms every few seconds on one USB port and not the other. This would _suggest_ I can catch differences around the ballpark of 100 Hz. I'm game for a randomized blinded test on 120 Hz refresh rate vs 240 Hz refresh rate. I would indeed be very curious to confirm I can tell the difference with a proper protocol. Many years back (we were on CRTs), I w…

> Many years back (we were on CRTs), I was in similar shoes, convinced my friend couldn't tell the difference between 60 Hz and 90 Hz when playing video games.

That’s a silly experiment. I could look at a CRT with a completely static image and tell almost immediately whether it was at 60Hz, 90Hz or 120Hz. Flickr at 60Hz was awful, 90Hz was clearly perceptible, and even 120Hz was often somewhat noticeable. And most CRT/graphics card combos would become perceptibly blurry in the horizontal direction at 120Hz at any reasonable desktop resolution, so you could never truly win. Interlaced modes made the flicker much less visible, but the crawling effect was easy to see and distracting.

Re: Toys/Lag: Jerk Monitor

#25

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were…

Higher refresh rates don't have to be perceptible to be useful: they can shift the balance in head-to-head gaming. Imagine 2 identical gaming setups with 2 players that have the same skill set. In an FPS game, you'd expect each of those players to win 50% of the games. Now switch one monitor from 120Hz to 240Hz. On average, the player on the 240Hz monitor will see their adversary 4ms earlier than the player on the 12…

Do any competitive FPS games actually render 240 different frames in a second? Because if both players’ hardware is doing 60FPS, that monitor difference changes nothing.

Re: Toys/Lag: Jerk Monitor

#26

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were…

The author didn’t say that they have a use for those 3200 updates per second other than as a workaround for some other issue. With a competently composited desktop and applications that pace input processing and frame generation well, and ignoring pointer acceleration, 1 correctly timed update per frame is enough. (As far as I know this does not exist from any vendor on a modern system other than for games, although really old Apple II-era software often got it right.). For acceleration, some pointer history is needed. And no one has a mouse that has an API that allows the host to pace the updates.

Presumably the 3200 Hz is needed for a combination of reasons:

- Under ideal conditions, if you want less than 10% variation in the number of samples per frame at 240Hz, you may need ~2400Hz. This effect is visible even by human eyeballs — you can see multiple cursor images across your field of view, and uneven spacing is noticeable.

- The mouse itself may work less well at a lower sampling rate.

- The OS and input stack may be poorly designed and work better at higher rates.

In any case, the application and cursor implementation are unlikely to ask for a mouse location more than once per frame, so the user is not really using 3200 updates per second, but that’s irrelevant.

Re: Toys/Lag: Jerk Monitor

#27
post #23

I can buy that humans can see at least 120hz at a minimum. 60Hz is the generally accepted threshold, but I’ve long suspected that 120Hz has mostly imperceptible effects that are still noticeable, if rarely. I can’t buy this: > I've also learnt I do benefit from the 8 kHz setting of my mouse, as even at 3200 DPI with fast & smooth motion, some frames still miss a pointer update It may be true that pointer updates were…

So tired of defending against this same, old, completely wrong intuition from people especially those saying "do the science" to justify their ignorance instead of looking themselves since the science has already been done and it's coming up on a full century old. From this one paper alone, humans can perceive information from a single frame at 2000 Hz. https://doi.org/10.1080/00223980.1945.9917254 Humans can read nu…

Best comment in the threads, IMHO. Thanks for the details.

Re: Toys/Lag: Jerk Monitor

#28
I bought a Logitech wireless mouse called the Marathon which boasted an amazing three-year battery life on two AAs. I initially thought it was broken; it had a maddening delay where the sensors turned off after a short idle time, so when I wanted to use the mouse, it didn't register the first movements since it had to "wake up".

This delay wasn't present on the Logitech gaming mouse I previously used, probably a combination of a high polling rate (500Hz) and a much longer idle delay. The battery life was also much shorter, only 250 hours on high-performance mode, but I just recharged a set of AA batteries every week so it was never an issue.

I ended up returning the Marathon mouse.

Re: Toys/Lag: Jerk Monitor

#30
post #24
post #11

Earlier quoted context omitted.

As per the post, I wrote this tool to confirm I was getting jerks of ~10ms every few seconds on one USB port and not the other. This would _suggest_ I can catch differences around the ballpark of 100 Hz. I'm game for a randomized blinded test on 120 Hz refresh rate vs 240 Hz refresh rate. I would indeed be very curious to confirm I can tell the difference with a proper protocol. Many years back (we were on CRTs), I w…

> Many years back (we were on CRTs), I was in similar shoes, convinced my friend couldn't tell the difference between 60 Hz and 90 Hz when playing video games. That’s a silly experiment. I could look at a CRT with a completely static image and tell almost immediately whether it was at 60Hz, 90Hz or 120Hz. Flickr at 60Hz was awful , 90Hz was clearly perceptible, and even 120Hz was often somewhat noticeable. And most C…

The effects you describe are specific to CRTs only, right? Caused by the electron beam effectively illuminating one pixel at a time?
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