Lacking Depth of Field(DOF)
Human eye is binocular vision. We use two eyes facing the same direction to perceive a single three-dimensional image of the object.
When objects have distance differences from each other, one of those objects will appear duplicated. For duplicated visions, I guess, human brain will recognize those areas as blurry version(out of focus).
DOF creates a sense of depth within the flat image, adding a huge realism to the graphic. Because in some way, it replicates the feeling of binocular vision.
It’s common to see DOF in real-life photos produced by a camera or phone.
Bicycles are focused.
The background and foreground are slightly out of focus
In cinematics, DOF is intentionally used to drive the audience’s focus around.
Lot of games use fog to create the sense of depth, not DOF.
DOF is such a great effect. It increases the realism of the graphics by add almost zero cost to the art production. But, why most in-game graphics don’t use it?
The short answer is to protect the playability.
When the player plays the game. The scene and the character are represented on the same screen. Most likely, there is some distance between distant objects and nearby objects.
But game software doesn’t know where the player is looking at. If the player’s eyesight is looking at something out of focus, this is problematic to the gameplay experience.
Character\Chian\Castle is focused at the same time
To avoid undesired blurry vision, game developers don’t use DOF effect in most in-game graphics. This makes In-game graphics feel less realistic compared to other digital graphic content like movie or general video.
However, VR game is a different story. Player’s view direction can be detected. Game software can use this information to implement DOF effects without hurting the player’s vision.
Mimicking Rather Than Mastering
Camera angle and scene sets in offline CG are fixed. Artists can carefully craft every detail inside the viewport.
A single complex CG frame can take hours to render.
https://sciencebehindpixar.org/pipeline/rendering
But in 3D games, players can move around and freely change the view angle.
It’s impossible to create in-game visual fidelity to reach CG level. Otherwise, it will take forever to finish and ship the game.
Also, if too much detail is added to the game. Game software may not be able to run smoothly on average devices. Laggy gameplay hurts playability a lot.
So, It’s a workload and computing power limitation for what developers can put into the game.
This is why the game’s graphics is always try to mimic the real world rather than fully creating photo-realistic content like cinematics.
Photo-Realistic Doesn’t Guarantee A Good Game
Scenes in real life can be boring to our brain because we see realistic scene all the time. Human brain love new graphic styles. Different visual styles bring a fresh feeling to the player.
Cinematic lighting takes a lot of effort to create the Cinematic feeling, it looks completely different from real life. But, it does look really good.
In fact, a lot of successful games have already been proven. Video games don’t necessarily have to be photo-realistic to be good. Stylized and cartoonish video games can be immersive too.
Photo-realistic is the only about the graphic. And, graphic is just a small aspect for developers to work with.
A good game has a lot more other important things to consider. Genre, narrative, concept design, sound, animation… Above all those tangible elements, providing a consistent gameplay experience is much more critical for a good game.