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3 inch extension with my 175 F8?

Started by Deshapiro, 11/04/2006 10:58PM
Posted 11/04/2006 10:58PM Opening Post
Hi All,
I'm finally getting my TMB 175 F8 up and running, about a year after it's purchase. The problem was the mount, since sold and now replaced with an AP 1200 (thanks Roland). When it was up, i couldn't get focus with most of the eyepieces (Televue). In speaking to the seller, who is a very straightforward and honest man, he told me that he had to use a 3 in. extension tube with his 2 in. diagonal, something that I will get this week. is this a common occurrence with this scope?

David Shapiro
Posted 11/05/2006 08:09AM #1
The TMB scopes are made to be binoviewer friendly.

The classic silver and white CNC models came with a 100mm extension tube. 60 and 30mm extension tubes were options.

Most of the folks I know have 2" Feathertouch focusers in back of the German ones, and we find the 60mm extension gives a nicer range of focus for that setup.

Posted 11/05/2006 08:49AM | Edited 11/05/2006 08:54AM #2
Here is a photo to illustrate what Mark is talking about. Although much smaller than yours this setup should give you a more clear picture. Long ago I bought all the extensions for my scope: 100mm, 60mm,and 30mm. The feather touch is just way to nice to pass up.
Take care,

Attached Image:

Nemo's attachment for post 108801

Danny Halstead
Moderator APM Forum