Quote:
Originally Posted by Wolf_Rider
yes, I saw your cheap trick there.... well done err except, you were saying FoV and bonocluars (zooming) were the same thing. All you have explained is the FoV of a pair of binoculars
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Ahh but there's more to it - FOV and magnification are LINKED, not just ASPECTS of binoculars you see!
Think deeply for a moment about what is happening. Light is coming in at certain angular limits - lets call this the 'angle of view' and in the case of our eyes its something like 90 degree cones for each eye - and the eye is focussing it onto a small sensor called the retina.
What binoculars, telescopes and magnifying glasses do is modify the Angle of view from which light is being collected, then REFOCUS it onto the eye and retina! Actually, so do photographic lenses.
Let me explain that a bit more. A telescope, for example, will grab light from a cone much smaller than our normal angle of view/field of view of 90 degrees per eye, then refocus and shift the light rays to project them onto our WHOLE retina! So it is as if our retina didn't change in size, but our eye focussed light from a much smaller cone - say a 5 degree cone rather than 90 degree cone - onto it.
The result is that the full visual acuity of our retina is focussed on a much smaller part of the world, and that part of the world appears to increase in size - it is 'magnified'.
In other words, they modify the ANGLE OF VIEW, also know as the FIELD OF VIEW, in order to magnify! IT is the very PRINCIPLE by which magnification works!
A related way of thinking about this is that we judge the size of something by its angular size - the amount of our view that it occupies. Our brain then figures out distance to interpolate actual size. OF course, our brain does not know exactly how much of our field of vision something occupies - it receives information from the retina. So it is actually the size of an image on the retina that is used to judge apparent size. This allows us to trick the brain by bypassing the normal cone of vision our eye projects onto the retina, and thus make a small angle of view occupy more of our retina! Thus, we have magnification.
ANGLE/FIELD OF VIEW is FUNDAMENTAL to magnification!
So now games -
Let's step back for a moment. You are sitting in a room with a monitor a certain distance in front of your of a certain size (lets assume you dont move closer/further). This monitor only occupies a portion of your angle/field of view, and thus only a portion of the image being projected by your eye onto your retina.
On this monitor (lets assume no bezel) is displayed a game with a certain amount of the world displaying according to the game's 'FOV' setting. What does this setting do?
Like a telescope or lens, except purely in the mathematics of 3d rendering, the FOV setting determines how much of the 3d 'scene' to render onto the screen (let's ignore perspective, ie, how straight lines appear and how things are distorted in it, which can of course be changed too). Its not actually a cone, unlike our eye, because the monitor is generally square, but it could be of course. But it is like a rectangular cone into the world.
If the FOV is set high, then a larger rectangular cone of the world is displayed on the monitor - but there is a cost - the monitor has certain acuity limits (resolution for example) and fine detail information is lost. Moreover, however, the monitor still occupies the same portion of the viewer's retina, so things will appear SMALLER than they would in reality, and with less detail (because our retina has acuity limits too).
If we set FOV to EXACTLY EQUAL the angle of view (and portion of our retina) that the monitor's image occupies, than projections of objects on the screen will occupy AS LARGE A PORTION OF OUR RETINA AS THEY WOULD IN REALITY. This is what I call a 1:1 view. The result? OBJECTS APPEAR AT THE SAME ANGULAR AND APPARENT SIZE AS IN REALITY! There's still some loss of acuity though, because the resolution of the monitor is likely LOWER than the visual acuity of our retina to discern details in the image of the monitor projected onto it - in other words, resolution on the monitor is not high enough to exceed the capabilities of our eye. But at 1:1, objects occupy as much of our retina and appear as large as they would in reality.
The big drawback is that only a small portion of the world or a few objects can be displayed on our retina - so we get 'tunnel vision', as you pointed out earlier. Such is the cost of 1:1 apparent size.
So what happens if we set FOV in the game LOWER than the angle/field of view the monitor occupies on our retina? Well we get a zoomed, or 'magnified' (and by this I mean a magnification of more than 1x) view, because the portion of the world displayed on our monitor now occupies a LARGER part of our retina than it would IF WE WERE IN THE GAME WORLD ITSELF AS HUMAN BEINGS. Remember that game worlds are basically representations of our physical worlds as if we occupied them!
This is basically as if we stood in the game world as human beings and use binoculars/telescopes. Now, the apparent size of objects is GREATER than it would be with the normal view of our eye, and so our retina's visual acuity and our monitor's acuity is bieng used to discern MORE detail in a SMALLER portion of the world. Just like telescopes.
Now there is an important aspect that I have not mentioned, and that is the tradeoff between realistic apparent size (ie 1:1 view) and realistic ANGLE OF VIEW INTO THE GAME WORLD. Because we are flexible and goal oriented beings, we do not necessarily put a premium on one or the other, and are able to adapt to either.
In other words, we might consider it more important to use our monitors to display a LARGER portion of the world and a LARGER FOV, despite the loss of visual acuity, because we dont actually need to see fine details to play the game!
OR, and this is why we use it in IL2, we might want to display LESS of the game world and use our monitor to display a SMALLER portion of the world to maximise the visual acuity of fine details, because we need these to play the game (for example gunnery in IL2).
Both are compromises that stem from the fact we are trying to play a game with a small monitor. And this is why I keep telling you that you shouldn't look at this in such an inflexible way - FOV is a compromise, THERE IS NO CORRECT FOV IN A GAME WHEN PRESENTED WITH LIMITED DISPLAY SIZE!