It is imperative to use all your equipment to get the best possible result when encountering any group of cultists, especially at cult outposts. Using the binoculars lets you get a better view of the enemies before they can detect you. It also “tags” them with a red outline so that you don’t lose their position if they enter a building or move behind a wall.
Tag as many enemies as possible before engaging them. Knowing where the enemies are headed or what cover they are hiding behind is an invaluable tool when planning your assault. In addition, enemies can also be tagged by placing them in the sights of any scoped weapon if you don’t wish to switch to your binoculars.