Chuck Dave Kriege's book contains a wealth of information and yes the table that goes with the template gives the proper offset for many different configurations. The template has a line drawn precisely done the major axis and one down the minor axis so it is easy to mark the offset. Clear Skies Don Colton -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com]On Behalf Of Chuck Hards Sent: Tuesday, August 12, 2003 9:00 PM To: Visit http://www.utahastronomy.com for the photo gallery. Subject: RE: [Utah-astronomy] Lasers and collimation questions Someone earlier in this thread mentioned a secondary mirror template for center-dotting purposes. Remember that if you have a fast system, the diagonal will not be centered. It must be off-centered slightly in order to provide an evenly illuminated focal plane. Hopefully the template will take this into account, I'm not familiar with the book mentioned. C. __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy