Show baby, don´t tell.

You ok, bro? That's a lot of feelings being caught for simply answering the OP's question.

All using the in-game camera. These are from Miiverse.

It's pretty much what Halo, GT,  Forza, PGR and some other games have as function for a long time. The possibility to stop the game anytime and use a free cam to “fly“ to any spot to take pictures from any angle you want (well, almost). I always wondered why Halo was for a long time only one of very few (if not the only, not sure) franchises on console which isn't about racing to have this photo mode with a free cam because it is awesome. 

Infamous can look obviously even better since texture resolution, lighting technology and stuff like that helps to take good photos in games as much as good cams with a good picture quality help for good photos and all these things are obviously better on a new console (the shoe photo wouldn't look so good on last gen with exactly the same function) but it's not new that people take photos in games like a real photographer in real life. The taken "photos" will simply look better and better with increasing graphics quality even if you said it's not about the graphics since pretty much all of the photos in op profit from graphics not possible on last gen. Without the good textures, many particles and good lighting they wouldn't look that good even if the "photographers" would still use the right angles.

Beautiful.

It isn't really new, but it's a new thing that people with no real interest in virtual photography are now noticing it, and identifies it as art.

Which is of course also a major milestone for the art form.

Not meaning to be a stickler here but the textures on some of those shots are hella distracting. IMO the WWHD textures we're better cause it blended with the Art Style of the game, but the environments of Pikmin 3 seemed to aim for realism hampered by blurry textures. Its definetly not DOF stuff either.

Also are those images compressed? Those jaggies don't seem natural.

Imagine if Sony takes this further and made a standalone game set in a virtual environment, with realistic people,wildlife,and buildings, with the sole of objective of taking photos.

What a surprise that photos taken in a last gen game don't look as good as photos taken in a new gen game with more particles, better lighting, better DOF and so on...That doesn't change that it's pretty much the same function just in a much newer game and this thread isn't about the graphics itself. So, if anyone thinks this is a new kind of art form he should think about some other games which are already older because they gave people already the same possibilities.

I can only see the last two pics and they are both in-game. As example the picture with the burning city i the background is the ap "Landfall"Not sure how the other pics he posted look but since Iceland knows Halo pretty good I'm sure he posted only in-game material. Probably most from multiplayer maps.

Is this in-game to you?

https://www.halowaypoint.com/de-de/games/halo4/filebrowser#?section=Image&SearchDate=0&SortBy=2&view-select=Tile&startIndex=384&details=5d851f1d-cfc1-4258-9039-9d17b879ed1f

Liar! That's a photo of the real Seattle