> Behalf Of Sean McCauliff
>
> What is the limiting factor on how big a telescope one can fit into a
> car (in my case this is a 98 Beetle)? Is it the ladder? The truss poles?
> Is there a big difference in optical quality between f/4 and f/5?
The mirror box and upper cage assembly. These are your biggest pieces.
Think of them as two boxes. You'll want to know the dimensions and weight
of these two pieces. You can always find a place for the tubes and step
stools.
Optical quality between F4.5 and F5 is fairly subjective. The difference
between F4 and F5 is a bit more noticeable. What you see is slightly more
coma in the F4. But most folks won't appreciate the difference. What you
get with a higher focal length scope is a taller scope. For that reason, if
you order a smaller scope, 15" and under, you might consider an F5 so you
don't have to bend over as much. On the other hand, you might like to sit
while you observe, so a short focal length instrument for the smaller scopes
would float your boat. On instruments larger than 15", you'll want to go
with an F4.5 or lower. That keeps the distance between the ground and the
eyepiece minimal
>
> At some of manufactures' web sites they mention 2" or 1.25" thickness
> mirrors. What is the difference between these choices? Durability?
> Does sweat pour down your face every time you need to move a thinner
> mirror?
The quality of the mirrors from experienced manufacturers is very good no
matter which thickness you get. If you go with a thin mirror, you'll need
full support for the mirror (it should not rely on a web sling or waffle
boards). You'll get temporary deformation of the mirror when you tip the
scope from vertical towards the horizon if you don't. If you opt for a
waffle bar or web sling, then go with the thicker mirror.
I'll tell you when sweat pours down my face.... lifting a heavy mirror!
Thinner mirrors weigh less and you have better control as a result when you
are loading and unloading.
You might want to take a look at my website for additional information on
the questions you posed. The URL is in my sig.
Michelle Stone
Custom Telescopes by Plettstone
http://www.plettstone.com/telescopes