The PSO-1 is a optical scope specifically designed for the SVD Dragunov as a telescopic sight by
Novosibirsk instrument-making factory around 1964, it has a x4 magnification. However, the common found in-game PSO-1 scopes only have a x2 magnification despite their description . The PSO-1 can be mounted on any Soviet or Russian made weapon such as the AK-74 and the AN-94 (although in SOC some weapons might not be able mount it) and features the same magnification as the SUSAT Scope. Although unlike the SUSAT the PSO-1's view includes a more visible drop compensator system which, with some practice, makes shooting at distant targets an easier task as one can easily adjust his aim when aiming at long range targets.
Standard x4 PSO-1 scopes can be found attached primarily to Dutyer rifles, as well as most Monolith and military soldiers using the AN-94 or AS VAL. Other versions are also available from traders. As usual, they don't give the weapon attached any bonuses aside from different sighting.
x5 fixed zoom PSO-1M scope - The standard scope from previous games. In the Inventory screen, the lens portion is colored blue entirely for easy identification. Used by many Loners, Bandits, Duty members, Military soldiers, and Monolith fanatics.
x2.7 PSU-1 scope - A close-quarters to medium range variant, with a fixed lower zoom. The lens portion has a small blue strip for identification. Sold by Owl in later stages of game and Hawaiian will sell if after assisting Freedom in faction war.
x5 fixed zoom NSPU-3 image intensifier night vision scope - Variant with passive, 2nd-generation nightvision enabled. The lens portion is a bright green. Occasionally sold by Owl after doing his missions. Sold often by Hawaiian after siding with any of factions.
x5 PSS-2X fixed zoom target optical scope with a built-in heat visor used to identify heat sources like the human body or mutants. - A scope with a built in target-identification system. Like the FT-200m and SVD's scope upgrades, it behaves like binoculars, locking onto and identifying subjects as friend-or-foe. Unlike the others, its end is a bright red. This is only sold by Hawaiian and the only way to obtain this scope is by getting the: A Wealthy Client achievement and a Friend of Duty achievement, along with that the scope will cost 11,000 RU. Note: A Wealthy Client achievement is not needed at later stages.
The magnification of the scopes in all three games is always less than it should be. 4x magnification models only have a 2x magnification, while the 2.7x model only has a 1.3x magnification.
There is a bug in Call of Pripyat with the Targeting and Night Vision PSO-1 scopes. When attaching either to a weapon and putting the weapon in a stash, the scope might turn into a regular PSO-1 scope. This can be avoided by keeping the scope unmounted while in stashes.
Probably to developer's oversight, if player will side with Duty in Yanov, he will not be able to buy PSU-1 2,7x scope from Hawaiian, but will be able to do so after siding with Freedom.