From: "Kristopher Barrett" 
To: 
Reply-To: "Kristopher Barrett" 


> Also any hints about pitfalls when doing a 16" F4 - 4.5 would be
> appreciated. I hope to have my grit within a week and I have heard that
> a fast mirror is harder to do.  I'd love to make it a F6 or maybe F7 but
> I would end up not using it because of ladders in the dark.  Brittle
> bones and ladders don't go well together.  The last time I fell off a
> step ladder I broke 3 ribs.

How about a slow mirror? Maybe an f10 gregorian or cass. Use a big
secondary, and drill the primary with a hole just big enough to mount a
tertiary mirror holder stalk. Put the tertiary mirror in front of the
primary. Send the focus outside the the tube near or at the balance point
of the tube.

if you put the eyepeice down near the mount, you don't have to climb ladders.



--
Regards,
Kristopher Barrett    http://www.cotse.net/users/kbarrett

--- BBBS/NT v4.00 MP