Re: Mars through LX200

It's the constant need to collimate them and their damned awkwardness
when being transported to remote sites that really bugs me. If they
could create an APO that didn't suffer from these problems, I'd buy one.
======================================

You sort of lost me here Pete, and perhaps a few others too.

Which scope is it, that you've determined is in need of constant
Collimation, the Refractor, or the SCT? And which do you claim is more
awkward to transport?

Refractors rarely need collimation if ever. Only when perhaps removing
the Lens/lens Cell for cleaning, should Collimation be checked/adjusted
if needed.

With an SCT, it's suprising just how well most of them do hold good
collimation. The biggest problem with SCT's IMO, is that people either
are unwilling to take the time, or don't have the expertise to properly
initially collimate an SCT.

Just a centered "Donut" is not good enough, and the other problem is,
once people get to fiddling with secondary mirror screws, they don't get
the proper torque on the adjustment screws, and hence wind up with a
secondary that has some slight play/flop. This is a recipe then for an
SCT that won't hold decent Collimation.

All Secondary Holder Screws must be tight, but not to the point where
you're just about ready to snap the heads off them. When one screw
needs, or I should say "Has" to be loosened slightly, the other two need
to be tightened to maintain solidity with the secondary, and proper even
torque at all three adjustment screws.

When doing the final precision tweaks to get exact Collimation, one will
turn the screws tightening them ever so slightly, perhaps a 1/16th, or a
1/20th of a turn at most, and NEVER by loosening one of them. All it
takes is a very slight "nudge" of the screw".

Good seeing, an equilibrated scope, and a solid mount are all pluses to
get the best.

If you are referring to an SCT being an awkward scope to transport, well
I'm not so sure about this either. Back in the old days, I used to
travel to dark sky sites on weekends (150 miles away) toting my Super
C-8 Celestron, with Tuthill Tripod, a plethora of eyepieces, my clothes,
etc in my Trans Ams (84+86), and once even toted the C-8 along in my '67
Corvette Rag-Top.

I'll agree that something like a C-14--Losmandy G-11 isn't exactly a
"small" scope set-up, to tote with a small car, but it is surprising
what people can squeeze into sub-compacts by wrapping the OTA in
Blankets/Quilts, and strapping her in like a passenger along for the
ride.

.

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