Re: ATM Effects of an inferior secondary

["Jan van Gastel" <jhm.vangastel@wanadoo.nl>]

If it (astigmatism) is not in the primary, it can also be in the primary
mirror cell or the lateral support of the primary. Before buying another
secondary it is wise to make sure it isn't caused by the cell or lateral
supports system.

Jan
http://www.geocities.com/janvangastel/
----- Original Message -----
From: "Michael Koch" <astro.electronic@t-online.de>
To: <atm@shore.net>
Sent: Friday, July 20, 2001 8:31 AM
Subject: Re: ATM Effects of an inferior secondary


>
> Yes, in case of astimatism you can rotate the main mirror. If the
astigmatism
> doesn't rotate, it must be in the secondary or in the eyepiece. Rotate the
> eyepiece to make sure that it comes from the secondary.
> In case of other secondary defects it's difficult to see in the eyepiece
> where the defect comes from.
>