Keywords: Secondary n Mount.png Sketch of the secondary and mount in a cut away tube en wikibooks Adrignola CommonsHelper 2006-11-19 Vorblesnak wikibooks en wikibooks English Wikibooks Vorblesnak original upload log page en wikibooks Secondary_n_Mount png 2006-11-19 00 22 Vorblesnak 643×304× 15092 bytes <nowiki>Reformat of the original with text and sub image</nowiki> 2006-11-19 00 19 Vorblesnak 643×304× 15092 bytes <nowiki>Reformat od the original with text and sub image attached</nowiki> 2006-11-16 04 31 Vorblesnak 469×260× 1732 bytes <nowiki>Sketch of the secondary and mount in a cut away tube</nowiki> Optics diagrams |