Khan Scope Centre AstroNotes April 7 2010

     I recall a while ago, I was at a Star Party, at
the Ontario Science Centre in Toronto, and there

were several telescopes that amateur astronomers were using to show Planets and
other Sky objects 

to members of the public. 

     There were all kinds of telescopes!....Newtonians
Reflectors, Schmidt Cassegrains, Refractors.

One in particular stood out it was a 12 inch Schmidt Cassegrain decked out with
just about every

accessory you could think of, and it sure looked impressive! Set up next to it
was a 4.5" Reflecting telescope. There was a long line up to look through
the impressive 12 incher, so I wandered over to the 4.5" reflector, which
had a much shorter line up. I took at Jupiter through it, and the image was well
defined, and the two satellite moons I could see where small, but pinpoint
sharp.

    When the lineup for the bigger instrument subsided, I
took a look through it, expecting to see an amazing image, and came away disappointed
in the lack of clarity. I asked the owner if I could do a quick check of the
collimation (alignment of optics) of the instrument, and sure enough, after
doing so, it was way out of whack!

The difference between the two scopes? One was well collimated (the
reflector) and the other was not.

Sometimes when you move your instrument from location to location, it gets
bumped around in the process and the main mirror and secondary mirror go out of
alignment. Or, out of collimation. This can severely affect your images and your
instruments performance.

How to collimate: Refer to your owners manual or the Manufacturers
website. Each instrument has it's

own particular quirks to alignment of the primary and secondary mirrors. In the
Case of refractors, if your instrument is collimatable at all, it will have
adjustment screws located in the front cell. 

Here are some useful devices that will assist with the collimation
process:

1) Bobs Knobs: These will work on most brands of instruments in the
commercial marketplace.

What they do is replace the small allen or phillips screws where your secondary
or primary mirror is mounted and give you easy to turn knobs, that allow
fingertip control for adjusting collimation:

We have a wide range of these available in stock, just give us a call 
(416) 783 4140 or 1 800 580 7160 or email

If you are on a budget, we also offer two other tools for Collimations
which are simple enough to use>

1) Sight Tube with Crosshair:  $39.95

2) Sky Mentor Laser Collimator: $65-  It is a basic laser collimator
that will do the job, but not as fast or accurately as the Hotech Laser
collimators.

To order any of the above lasers, call 1 800 580 7160 Toll Free or local
416 783 4140

Khan Scope Centre also offers numerous services for all kinds of
telescopes, including Collimation.

Just bring your Optical tube assembly  in, with the Diagonal you are
using,  1.25" or 2" with that particular scope, if applicable.
(we don't require the tripod or mount).

If your instrument requires cleaning, we can do that at the same
time.  The cost varies depending on the amount of time involved, the size
of the telescope, etc...

Khan Scope Centre   3243 Dufferin Street  Toronto Ontario
Canada M6A 2T2



Toll free: 1 800 580 7160    Local: 416 783 4140  fax: 416
352 1701

email: info@khanscope.com

website: www.khanscope.com

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