Yet Another Collimation Topic

[RMcCallum]

I have looked on other topics and threads to find an answer to my problem, but alas I have been unable to. My apologies if I am reposting a topic previously covered.

Since I have recieved my scope (see signature) back in the summer of 2012, I haven't really given much thought to its collimation. However, recently with the cloudy nights and boredom, my mind has drifted to fine-tuning my scope and buying stuff I probably don't need .

I have read Astro Babys Collimation Guide and it looks like I'm gonna need a Cheshire and a Cap, not a problem. My problem is the Primary Mirrors centre spot, mention in the guide. My wee scope, as far as I can see does not have one, and I'm pretty sure I need one. My questions are as follows:

1) Do I need to remove my primary to put one on?

2) How do I remove my primary if I need to?

3) What do I use to add a centre spot?

Thanks for taking the time to read.

[nederman63]

I was looking at this the other night, luckily enough though my scope does not need it, yet, but one Web page said about using a round sticker, the type you use on paper for a ring binder. How you centre it or get it on the mirror without damaging it though I don't know. Anyway I'm a newbie so ignore me and wait for a intelligent answer:-)

[BrettP77]

Haven't done it myself yet but this looks like a pretty good guide.

http://www.garyseronik.com/?q=node/168

[RMcCallum]

That looks like a great guide thanks Brett, it never occured to me to google it. *FacePalm*

[jimbooz]

I went for a cheap seben collimator off Amazon. It does the job but needed collimating itself using the four nails method! Check out youtube for details.

Jim

[Astro_Baby]

http://www.astro-baby.com/TAL%20Telescope%20Rebuild/Telescope%20Mirror%20Cleaning.htm

take a look there for another method of centre spotting. Bit more demanding

[Twiggles]

Actually thinking about collimating my scope as well. Had it a couple of months now so wouldn't hurt to do it, plus it has to be done at some point anyway right? Might as well bite the bullet and give it a go!

I'm thinking of getting this to help out:

http://www.firstlightoptics.com/collimation/rigel-aline-collimation-cap.html

and this:

http://www.firstlightoptics.com/collimation/cheshire-collimating-eyepiece.html

Any thoughts on either of these products? I'd prefer to stay away from laser collimators for now.

[JD75]

I did it recently myself using both the Cheshire eyepiece and collimation cap. I followed Astrobaby's guide and to be honest, it was really straightforward to do. The scope was miles out, but with some gentle tweaking, I was able to work out what needed to be moved to get everything lined up perfectly.

It was a lot easier than I thought it was going to be and to be honest, my only piece of advice would be to take it slowly and see what happens with each adjustment you make. Hopefully you'll have no problems.

[Apollo Paul]

This you tube video might help.

[Moonshane]

to create an accurate centre spot there are a couple of easy methods. you always need to remove the primary which is easily done - it's worth it with an f5 scope.

1) measure the diameter of the primary (plastic ruler only) and use a large compass to draw circle on paper. cut this out, place it squarely on the face of the mirror and use the pin hole to mark a dot with permanent marker - as small as you can. check several ways that the dot is central with the plastic ruler, then fold the circle in quarters, cut a small hole out of the point and put the paper back on the primary (unfolded of course). then use this to lean on while accurately placing the reinforcing ring around the dot you made with the dot in the centre.

2) draw round the mirror onto paper, cut this out, fold into quarters accurately and then snip off the very tip pf the point. then follow as above for the rest.