Depth of Field is the blurring effect to draw focus onto an object. Like when you ADS and everything except the area around the gun in your hand becomes blurred. The assets are already visible and loaded, and the effect is a shader.
Draw distance usually effects whether something is rendered in the distance at all. LOD (level of detail) allows for higher detailed models (higher textured, more polygons) to be swapped with lower detailed versions of the same model as their distance increases. Adjusting an LOD slider would usually determine how far a model can get before it starts progressively swapping to the lower detail ones.
Depth of field prevents assets from loading unnecessarily.
Depth of Field is the blurring effect to draw focus onto an object. Like when you ADS and everything except the area around the gun in your hand becomes blurred. The assets are already visible and loaded, and the effect is a shader.
You might be thinking LOD distance or FOV.
It can be used to disguise low LODs too.
I might be thinking of LOD. Though, it also could have just been something like draw distance. Not like games are 100% consistent.
Draw distance usually effects whether something is rendered in the distance at all. LOD (level of detail) allows for higher detailed models (higher textured, more polygons) to be swapped with lower detailed versions of the same model as their distance increases. Adjusting an LOD slider would usually determine how far a model can get before it starts progressively swapping to the lower detail ones.