Hi Mark; With all the scopes I've made, I just made sure that the eyepiece which needs the most "in" travel, comes to a focus near the racked in position. Don't forget to also test your eyepieces with your barlow if you have one! It can get costly to not get this right if you cut the tubes too short; so take your time. But also consider that you can adjust with shims if you end up needing the tubes to be a bit longer (ask me how I know...) Mat -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Mark Shelton Sent: Thursday, April 28, 2011 6:31 PM To: Utah Astronomy Subject: [Utah-astronomy] Dob Help? Hello all, I am just getting ready to cut my trusses for the dob I am making. The question I have is where to make the eyepieces I have come into focus. I have read that you use a 2" eyepiece racked all the way in and cut your trusses when it just reaches focus. Then I ready just the opposite. You should cut your trusses so everything is in focus with your eyepiece racked all the way out. What are your feelings on the matter. I feel I should make eyepieces come into focus in the middle of the travel of the focus-er. ?????? Thanks for your help in this matter. Mark Shelton _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php ---------------------------------------------------------------------------- This message and any included attachments are from Siemens Medical Solutions and are intended only for the addressee(s). The information contained herein may include trade secrets or privileged or otherwise confidential information. Unauthorized review, forwarding, printing, copying, distributing, or using such information is strictly prohibited and may be unlawful. If you received this message in error, or have reason to believe you are not authorized to receive it, please promptly delete this message and notify the sender by e-mail with a copy to Central.SecurityOffice@siemens.com Thank you