View Single Post
  #28  
Old 24-02-2014, 10:36 AM
Satchmo's Avatar
Satchmo
Registered User

Satchmo is offline
 
Join Date: Dec 2005
Location: Sydney
Posts: 1,883
Quote:
Originally Posted by Paul Haese View Post
I am not sure. In the Tak scope I can see the mirror clips on the side of the primary. And; the secondary baffle does not appear to be causing a huge obstruction in the Tak scope. Mathematically the secondary is 5mm further away in this scope too. So if anything it should present less of an obstruction really??
If that is so then the only other thing that could cause an abnormally large secondary shadow is a correction error. You mention a 5mm change of mirror spacing in the new incarnation. I don't know how tight these spacings need to be held to remain with good correction. A star image racked the same amount in mm the other side of focus would show if the abnormally large secondary shadow is a correction error or a vignetting issue. If it is a vignetting issue the appearance will stay the same on the other side of focus.
Reply With Quote