SCT Collimation

How well do Celestron SCT's hold collimation typically? Do they require
frequent re-collimating, if transported and used gently, or is collimation a
once-every-few-months sort of thing?

Thanks!!

Rank Amateur wrote:
How well do Celestron SCT's hold collimation typically? Do they
require
frequent re-collimating, if transported and used gently, or is
collimation a
once-every-few-months sort of thing?

Thanks!!

I haven't had to recollimate mine in over a year. But, unfortunately I
don't
get it out very often, especially recently. But, it holds collimation
extremely well.

tedkord wrote:
I haven't had to recollimate mine in over a year. But, unfortunately I
don't get it out very often, especially recently. But, it holds
collimation
extremely well.


Does your scope hold collimation when the primary mirror flops (i.e., when
the scope passes from E to W or v.versa)?

Rank Amateur wrote:
How well do Celestron SCT's hold collimation typically? Do they require
frequent re-collimating, if transported and used gently, or is collimation a
once-every-few-months sort of thing?

Thanks!!



In three years, with frequent use, my C-8 was collimated twice, about
three days apart. Once to get it close, then again when the seeing
improved to provide steady diffraction rings around stars. I haven't
needed to touch it since.

Clear Skies,
Uncle Bob

you should be checking it every time you use it just likeyou zip up your
LL Beans.



Rank Amateur wrote:

How well do Celestron SCT's hold collimation typically? Do they require
frequent re-collimating, if transported and used gently, or is collimation a
once-every-few-months sort of thing?

Thanks!!

A member of our observing group has a 15 year old C8 that has never
needed colimation! Ans we look to see if it needs it quite often.

My 13 year old C11 needs colimation about once a year, but at this
level we are talking about colimation errors so small that the typical
observer could let it go for years at a time.

Super picky observers will end up colimating every time the sky is good
enough to colimate. With a C11, these kinds of skys only show up a
dozen times a year, and we only end up observing on 2 or 3 of these
(moonless) nights. With a C8 many nights (25%) are good enough to
colimate.

The answer to this question is "depends upon who does the collimating".
If done properly it almost never needs adjustment. Proper tension on
all three screws is the key.

Gil