There is no set range limit for a periscope; it's affected by many factors, weather conditions playing a large part.
In addition to weather, the height of the periscope above the water, sea state (height of the waves), target profile (large, small, low or high in the water), daytime or nighttime, all affect a periscope's actual range.
The captain of the submarine raised the periscope to see if there's danger.
When at periscope depth, they look through the periscope. It is a prism arrangement that allows good vision around the area. It also provided for gauging distances with a built in range finder.
The submarine
The submarine's periscope and radar mast are damaged.
Periscope
red
Periscope.
The periscope is used by the submarine to look around the surface of the water, while the rest of the submarine is under water. It makes the submarine harder to find and destroy by enemy antisubmarine warfare. The periscope might be just a simple set of mirrors or it might have a "heads up display", similar to HUD found in some combat aircraft, that give the range to the target, as well as a magnifying glass that also makes the target easier to see, similar to a pair of binoculars.
If you mean in the periscope, two.
i think you mean the 'periscope'.
In paintball wars, a periscope is a handy way to look around a corner without getting shot. With only its periscope out of the water, a submarine was nearly impossible to spot at a distance.
The periscope of a submarine is located in the sail, also known as the conning tower. This structure is situated above the main hull and contains various equipment, including the periscope, which allows submariners to observe the surface while the submarine remains submerged.