So many people keep repeating this myth all over the Internet, that I decided it would be a good idea to bust this myth right here, once and for all. So, let’s get started.
First of all, the core statement is a nonsense. There have been many reports from different reaction tests that people can react to visual signals in less than 1 ms - this corresponds to 1000 FPS.
Now, where did this myth about “60 FPS” came from in the first place? Most LCD monitors today, let alone 10 years ago, have refresh rate of 60 Hz. On such monitor, no matter how much FPS your application, such as video game, has, you will see only 60 Hz, and additional frames will be ignored. On such monitor, even if your game has 1000 FPS, you will still essentially see 60 FPS.
Now take an old good CRT monitor. CRT monitors are good for this because their image is fully dynamic, that is every frame is drawn from scratch, while LCD monitors do not effectively draw frames that are not very different from each other, they only draw the difference. In dynamic scenes CRT and LCD monitors are similar in this regard.
Most good CRT monitors used to show 85-120 Hz. When you set your refrest rate on such monitor to 60 Hz, you can clearly see extreme flickering. When you set 85 Hz, flickering becomes bearable, but still noticeable. 120 Hz - flickering is almost gone. The difference between 120 Hz and 240 Hz is still noticeable if you place two monitors close to each other and stare at them attentively, but it is very slim.
Let’s return to LCD monitors since that’s what most people use today. I want to make a very important statement here that people arguing about FPS often do not fully understand:
How much FPS you can see depends on the scene you watch.
Imagine if the scene is just Windows desktop, without any activity on it. How much FPS do you need? Right, 0.
Now, imagine if a dot moves on your screen at speed of 1 pixel per second. Since the monitor cannot show “half pixels”, you don’t need more than 1 FPS to see this as perfectly smooth as your display resolution allows.
Imagine now an object that moves from the left edge of your screen to the right. It goes at speed of 200,000 pixels per second, while you have a resolution of 1920x1080. How much FPS do you need to notice this object? Since it shows on your screen for 1080/200,000 = 5.4 ms, you need 1000/5.4=186 FPS to consistently see it on your screen.
What does it all mean? If you use your usual 60 FPS, in about 66% cases you won’t even pick a glance at this object. If you use 240 FPS, however, you will see it cross your screen every single time. And, since your eye is theoretically able to see much more FPS than that, you WILL actually see this object.
So, here is the thing. When you say that you cannot see any difference beyond 60 FPS, first of all make sure that you are actually looking at more than 60 FPS. You cannot see more than 60 FPS on a 60Hz monitor no matter what, since the monitor itself will always show exactly 60 FPS. Then, make sure that you are actually looking at highly dynamical scenes, not just looking at your desktop moving icons around (although between 60 FPS and 120 FPS, I bet, you will see the difference even there). Finally, account for the habit: if you’ve been using 60 FPS for 10 years and then suddenly receive a 120 Hz monitor, you might not see the difference clearly right away since your eye is used to staring at the old screen. Give it some time, maybe, a day - then revert to the old refresh rate, and you will IMMEDIATELY see a HUGE difference by just moving mouse cursor around. You will see so many frames skipped, you will be shocked that you’ve never seen them before.
So, how many FPS do we need? Depends on the applications you use, of course. If you are interested only in web browsing and office work, you are unlikely to really need anything beyond even 30 FPS. If you play some slow-paced games like Hearthstone, 60 FPS is fine. If you play all kinds of games, including RPG, FPS, RTS, etc., 120 FPS will benefit you a lot. And if you are a hardcore FPS gamer, the more FPS you have, the better, 240 FPS and beyond will be just perfect.
TL;DR:
- Human’s eye can see up to 1000 FPS and, perhaps, above.
- 60Hz monitor will always show 60 FPS, no matter how much FPS your game is able to provide.
- High refresh rates are noticeable only in dynamic scenes; in slow or static scenes you rarely will see any difference beyond 30 FPS.
Also, notice that it is my personal understanding of the problem. I may be wrong somewhere - if so, please feel free to correct me. Just remember: before saying stuff like “I cannot see anything beyond 60 FPS”, make sure that you’ve actually tried it on scenes that are able to deliver a real difference - I guarantee that you will see a difference up to 200 Hz, at least, with the right way of testing.
author : May90