EntityQ189619· pop 6· linked from 8 articlesstar diagonalSign in to saveaccessory for astronomical and geodetic telescopes for observing zenith nearby starsConnectionsmirrorEntitytelescopeEntityzenithEntityoptical dispersionEntityfocal lengthEntitystar chartEntityeyepieceEntitychromatic aberrationEntityf-numberEntityobjectiveEntityfield of viewEntityspotting scopeEntitypentaprismEntityMaksutov telescopeEntitySchmidt–Cassegrain telescopeEntityAmici prismEntityOptical pathEntityHerschel wedgeEntityAmici roof prismEntityCategoriesOptical components