Platypotamus

Once you have done any sort of development work, it becomes difficult to play a game without entering developer mode here and there.  This happened to me while playing Red Dead Redemption as I noticed a couple of things about the camera, and I figured I might as well share my observations.  So I sat down and did some tests with it, and noted the results.

The camera is, of course, freely rotated with the right thumbstick.  If it is left "out of position"--that is, not directly behind John Marston--it will be pulled back into position as the player walks along, unless the player actively maintains the unorthodox position.

One of the biggest challenges when implementing a third person camera is what to do about intersecting objects--those that come between the player and the camera.  Rockstar San Diego opted for "snapping through" intersecting objects, rather than fading them into transparency.  This means that if there is an object between the camera and the character, the camera quickly snaps to a closer zoom level just on the other side of the intersecting object.  Moving either the character or the camera so that the object no longer interferes causes it to snap to the default position.  The sudden camera move can be slightly disorienting, but is not particularly glaring.  Some objects are considered to interfere, others are not:

• Environmental objects all are considered interfering (buildings, trees, random art props)
• Doors are considered interfering, but the camera can zoom back out once the door opens
• Windows are considered interfering, despite being transparent, even if they are broken out by the player's actions
• Horses and people (and presumably wild animals) do not interfere, and can pass between character and camera without moving it.
• Stagecoaches do interfere with the camera, but the horses pulling them do not

When the player enters targeting mode, the camera will never snap due to interfering objects, and any such objects simply block the player's view; they do not go transparent.

Speaking of targeting mode, when the player switches to this mode, the targeting reticule attempts to position itself in the center of the player's current camera facing, rather than having John Marston simply target in front of his own facing.  This means that if the camera is looking back at Marston's face, entering targeting mode causes him to turn around, while maintaining the camera's current position and orientation.  If the player's camera is oriented in a non-aimable direction (notably, directly down, at least when using a rifle) the camera angle is preserved, but no reticule is displayed, to indicate that the player cannot target this location.  Moving the camera to a targetable position brings the reticule up, and the camera can be moved back into the ineligible location after the fact.

The developer acknowledges the camera's existence in the world in a couple instances.  Certain activities can cause blood splatter to hit the camera.  These include getting wounded, skinning animals, and messing up in the Five Finger Fillet mini-game.  Additionally, water can splatter the camera.  Thus far, this has only occurred during rain storms.  Notably, water only gets on the lens of the camera when it is inclined upwards, a keen moment of attention to detail by one of the designers on the project.