Re: [APML] Focusing and temperature change issues during an exposure- advice wanted

[Alan Voetsch <critter12952@yahoo.com>]

Hi Matt,

--- Matt BenDaniel <matt@starmatt.com> wrote:
> That might be
> handled by an OAG, but if you're using a guide
> scope, it may be best not to have the focus adjust
> during an exposure.

The Taurus is an OAG, no guidescope for the SCT. 

> I anticipate the temperature change and adjust the
> focus to where I estimate it will be during the
> middle of the exposure, or at least compensate
> slightly in that direction. Most scopes get shorter
> when temperature falls. I adjust the focus just a
> shade to the outside.

I'll look into this. Although, if I'm not mistaken,
focus can move either way on my scope. I'm sure there
is more than one reason for that.

Thanks,
Alan

> At 01:44 PM 11/13/2002 -0800, Alan Voetsch wrote:
> >...what's the best way to make sure that focus and
> >temperature related issues are not screwing up a
> great shot?



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