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I'm scared I have attained the debilitating Collimation Syndrome ( HClV-1a : Human Collimation Virus strain 1a. - mild/severe).

Was out with Calpernia yesterday (ehm..my scope's second name..) and I decided to correct her eyesight..again..

(She's now 11 month's old...her first name is Sky, her surname Watcher, 10" of joy..)

I followed my baby's collimation guide (I mean Astrobaby..sorry..)

And to my surprise the collicap worked (which I have never tried before) very well...

I could see all the six mirror clips on my primary mirror..but it seemed like the clips were not

evenly spaced with reference to the side of the secondary mirror's edge.

As explained in AstroBaby's guide..

"The photograph to the left shows what the actual view should be like at this stage of the process.

  Note the three mirror clips are all visible and are all equally close to the edge of the secondary mirror and the secondary is

  showing round and centred to the focuser tube ( the dark area at the edges of the picture)." (Astrobaby, 19..)


source: http://www.astro-baby.com/astro_baby_telescope_help_and_advice.htm. Collimation Guide for Newtonian Reflector Telescopes.

I checked with my Cheshire...it showed that (according to the Cheshire) the secondary didn't appear

quite cylindrical in the tube.

So now I recollimated the whole thing...using my trusted Cheshire...and everything is bang on..

When I insert the colli cap thereafter I can see all the clips, almost all the same size, but still with a slight

miscorrection of spacing around the secondary's edge..

Maybe I'm just getting old, and my eyes are tired..

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Your collimation sounds as if it's spot on, next time you have your scope out

for a session try doing a star test, that will tell you if it's spot on, at the bottom 

of Astrobaby's guide it shows you how, make sure your scope has cooled to

ambient temperature first, but it sounds good to me others may think not, 

I use both cap and Cheshire, and I am always happy with mine, the star test

will be the judge.  

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hello ronl..

yes..I was thinking the same thing..

but can't really do a star test as I have no stationary star in the southern hemisphere...

I tried...but have to correct my alt/az the whole time...

the star tests that I have done seem to confirm my suspicion, collimation is very good..

thanks for the input !

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Looks pretty good to me.

Download Als-Collimation-aid and over lay it on your images.

The concentric circles will help you.


Of yeah I use coloured card for differentiating.

Edited by RichM63

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ehm..just to be clear..

the pic in my post was taken from Astrobaby's website...

I used it to illustrate my point...


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