What type of Collimating Eyepiece?

[nebulosity. (Jo)]

G'day

I've built an 8 inch F6 newt and am wondering what is really needed to to help get good collimation with it, I have looked up collimators but am a bit confused as to what type would be best, it seems you can go from simple peep hole ones to complex laser types. What would I need?

I would prefer not to buy one so a bit of an idea on a design that I could build would be cool

Cheers
Jo

PS I have access to a wood and metal lathe if thats any help?

[wavelandscott (Scott)]

All budgets can be met with a little effort...

Remember there are two mirrors that need to be aligned...the primary and secondary...

Some tools work better for some tasks...

A plastic film container with a hole drilled in the bottom will work a treat.

An Orion collimating eyepiece (or similar name) can be picked up at Bintel (maybe others)

Or lastly a laser tool of some type (many on offer).

I am a fan of the Orion collimating eyepiece...rock solid and never needs batteries or alignment...I use mine most every time out.

I also have a Catseye System and a Howie Glatter laser and tu-blug...both of which give outstanding results.

That said, a film canister with a hole drilled in the bottom will do a decent job in a pinch.

[bytor666]

You should be fine with a collimation cap as you are at F/6 and collimation isn't super critical. I have a 10" F/4.7 and I also use a collimation cap and the center spot on my 10" primary. I made my own out of a film canister cap. I drilled a small hole and placed a reflective ring on the underside of the cap.

To finalize my collimation, I line up both rings.

Just make sure the lid on the back of the scope is off to let a bit of daylight through the back of the mirror so the center spot on your primary is viewable, (just be careful that it is not a sunny day and the sun can be seen).....I fear the dangers of a bright sun anywhere near my telescope or primary mirror. I will do this on an overcast day in my back room with my bright blue curtains shut.

Works for me.

[nebulosity. (Jo)]

Thanks a lot Guys!

It sounds like I should have no worries with a simple peep hole type eh? I have centre spotted the primary mirror so the reflective ring sounds like a cool idea, hopefully I'll be able to make something in the next few days so I'll let you know on how it goes.

cheers
Jo