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An occulting bar is a bar-shaped attachment for a telescope designed to block light from a bright object in view so that other objects can be seen more clearly. Like a coronagraph, it is a type of occulter, the terms essentially suggesting their shape: a rectangular bar shape versus a circular shape such as would be used to block out the Sun. The reason for the bar shape is convenience in mounting: occulting at/within the telescope must be done at (or very near) a focal plane which places practical limits on the means of mounting an occulter, and blocking a strip across the field of view often serves the purpose. Occulting bars are sometimes used with large research telescopes (HST STIS includes one) and are easily devised for small amateur telescopes, typically to see objects that, within the celestial sphere, are very near a bright star.