Thanks Jim. I'll take a look. -----Original Message----- From: Jim Gibson [mailto:xajax99@yahoo.com] Sent: Saturday, November 22, 2003 1:45 PM To: utah-astronomy@mailman.xmission.com Subject: [Utah-astronomy] Roof Prosm Chuck & Kim I saw your post that mentioned roof prisms. I had never heard the term so I decided to google up some information. There are tons of sites talking about roof prisms and two that I thought might be of interest are included here: Roof physics http://www.kireinc.com/english/Roof_Prism.htm <http://www.kireinc.com/english/Roof_Prism.htm> Comparison http://www.birdwatching.com/optics/roof_vs_porro.html <http://www.birdwatching.com/optics/roof_vs_porro.html> After reading several articles, I am not sure how roofs differ in appearance or construction from the Porro. The roofs look just like the prisms I had in and old pair I once had. Jim _____ Do you Yahoo!? Free <http://us.rd.yahoo.com/slv/mailtag/*http://companion.yahoo.com/> Pop-Up Blocker - Get it now