https://wccftech.com/galaxy-s11-camera-features-5x-zoom-ois/

So far, a couple of possible Galaxy S11 camera features have highlighted the possibility of a unit capable of delivering 5x optical zoom. In contrast, the Galaxy S10 only sports a 2x telephoto lens, making the 5x zoom addition a significant upgrade for the Galaxy S11 lineup’s arsenal. However, a fresh rumor claims that in addition to the zoom extension, it looks like Optical Image Stabilization (OIS) might complement that 5x zoom feature, turning it into in a very capable single camera unit.

Most recent Samsung flagships offer dual OIS or single OIS for it rear camera array. This ensures that even when you are moving around or your hands are shaking, you are able to capture fairly clear images even if it’s a zoomed-in shot. However, since the Galaxy S11 is expected to have a periscope camera module that lays parallel to the phone so that there is no protrusion and uses a mirror to reflect light, it wasn’t clear if OIS will also be a part of the Galaxy S11 camera features.