Reality and screens are two very different things that are hard to compare. Therefore, one of the first questions that comes to mind when playing a First Person Shooter is "What FPS Is Real Life?". The answer to this question varies from person to person and also depends on what you are looking for. If it's realism you want, the real world will never be able to deliver it 100%.

However, if you are not too keen on technicalities but value gameplay over anything else, then some great games offer within their game mechanics something akin to reality. This article breaks down various elements of realism across various shooters to give an estimate about how close each game gets towards being realistic.

How many FPS can the human eye see?

Before we talk about how games measure up to reality, let us first understand how the human eye works. A lot of you have heard this before but for those who haven't here is a short explanation. Our eyes have a retina that comprises photoreceptor cells called rods and cones. Rods are specialized in seeing at night while cones do so during daytime and also provide color information to the brain. The ratio between these two types of cells varies from person to person but on average if you go out into broad daylight then around 400-800 thousand rods will be present in your eyes per square millimeter of the retina. Also, it has been estimated that cone density peaks around 555 pixels per degree squared (ppd), after which it starts declining. In general, the human eye can see around 20-25 Fps when looking at a screen in broad daylight.

However, to avoid taking into account individual variations, eye experts have standardized this number to 50 Fps as the minimum requirement for a video or image to be termed as "crisp and flicker-free". Anything below that threshold in terms of frame rate will cause the person viewing it to experience fatigue due to flickering which is why movies are shot at 24FPS. But you'd be surprised at how much our eyes can take. Also, if the object being viewed is moving then this limit goes even lower which is why games generally render anything beyond 55 Fps. This also happens because our eyes, just like the rest of our body, do not respond well to quick and repeated movements.

Aspects of vision

The first thing to note is that we experience vision in different ways. The difference between detecting motion and light detection isn't significant. Another distinction to make is that various portions of the eye perform differently. The middle of your vision excels at various things, while the outskirts are limited. And there are physical, biological limits on what we can perceive. It takes time for the light that enters your cornea to be converted into information that your brain can use, and our brains only work efficiently at a certain speed.

In PC games the developer can adjust the maximum frame rate where a speed of 55 Fps would be "acceptable" because that's the limit set by eye experts. This, however, can't apply to console games due to technical limitations. In console games, your eyes have no concept of what a video game is running at so it's up to developers to decide on how they want their game to play in terms of response time and visual quality. You'll find this aspect in almost every modern FPS out there across all platforms including PC and consoles. Now let us explain how these individual elements come together when we talk about shooters in real life and video games.