Red Dot Sight:
In simple words, a red dot sight can be described as a non-magnifying reflector sight used to aim at a certain target with precision level which can not be achieved when aiming with bare eyes. Considering the fact that a red dot eyes does not magnifying the target, a shooter should have no focus issues when aiming at a certain target through a red dot sight.
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Holographic sight, more formally known as holographic weapon sight or holographic diffraction sight is a gun sight which simply creates a reticle image of a target on a glass optical window so that it becomes easier for the shooter to accurately aim at the target. Holographic sights do not magnify the target in any way.
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