EntityQ600076· pop 9· linked from 5 articlesHerschel wedgeSign in to saveoptical prism used in solar observationConnectionsInternational Standard Book NumberEntityrefractionEntityJohn Frederick William HerschelEntitysolar telescopeEntityobjectiveEntityneutral density filterEntitystar diagonalEntityCategoriesAstronomical imagingAstronomical instrumentsPrisms (optics)Solar telescopes