Metro: Last Light developer 4A Games has taken to their official Steam community page (via VG247) to outline that the lack of a FOV slider would actually be detrimental to the game, warning that "changing the FOV would break all the cut-scenes and animations."

In a lengthy note on the page, the 4A team revealed that the reason Metro: Last Light relies on a fixed field of view is due to "3D elements like the watch and weapon ammo that need to remain visible." According to the post if a FOV slider was introduced - which apparently they tried doing in development - you would be able to "see inside Artyom's arms, or they would appear to float in the air in front of you."

Due to the nature of how the game was developed, with the heavy reliance on the fixed FOV setting during first-person cut scenes and cinematics, 4A have not yet found a permanent solution for issue. The team has however admitted that due to the large community outcry for a FOV setting, the next update for the PC version will include the ability to directly change the FOV through the .cfg files.

The note does conclude that while this option may satisfy those in need of FOV changes, it "may well trigger a number of issues listed above - you have been warned!"