Collimating - what to get?

[sejanus]

hey guys

I have never collimated a scope before, and have no idea regarding it.

I have a 8" newtonian arriving in a couple of weeks

Do I get the laser collimator tool on the bintel store or is there something better? What do you recommend?

thanks

[rmcpb]

Two tools will make it much easier.

First the Orion collimating Tool (https://www.bintelshop.com.au/Product.aspx?ID=5508) to get the secondary set up and aimed at the primary correctly.

Second the Laser Collimator to ensure the light from the primary is coming straight back up to the secondary.

When that is done you really only need to check with the laser at the beginning of each session to ensure you have the best images possible.

Cheers

[ving]

i use a cheshire :)

[sejanus]

Thanks - so I get the Orion tool *and* this one?

https://www.bintelshop.com.au/Product.aspx?ID=6737

cheers

[astronut]

You only need the uncomplicated Cheshire, everything else is just unnecessary:)

[sejanus]

mmmm, got a web linky? :D

[ving]

linky? thats what the orion does/is.

andrews com used to sell one for about $30 but i dont know if they still do.

[astro_nutt]

Hi sejanus..
I use a cheshire crosshair to align the seconday to the focuser..(so the secondary appeas perfectly round) and also to view the entire Primary in the Secondary..(you can check this by focusing fully in and out)
I then adjust the primary so that the cheshire's crosshair sit over the reflection of the secondary's 4 spider vanes..then to adjust the reflection of the cheshire's angled reflector on top of the the primary mirror's centreing ring whilst looking through the cheshire itself..this should align the secondary to the primary...from then on you could use a laser to check and correct your setting when required.
Just a few helpful hints..
If you do buy a laser..be sure it can be collimated also!!
Makes sure you perfom the collimation in quiet conditions..without pets etc.
Always collimate with the optical tube horizontal..so that nothing can fall down the optical tube and strike the primary mirror.
Buy a set of watchmakers screwdrivers and use the appropiate allen headed one to adjust the secondary's grub screws.
Keep a record of the number of turns for each of the 3 secondary screws.
Do exercise care and don't overtighten.
Use a table lamp behind a white sheet to view the primary/secondary reflections.
Be sure to take a break or three...
After it's done..give yourself a pat on the back!!!...cause it does get easier!
Cheers!

[astronut]

:thumbsup: :thumbsup: :thumbsup: :thumbsup:

[astronut]

Just one other thing SJ,
I would replace the secondary and primary knobs. The reason for this is that you have to use tools to set the alignment and they can be a real pain in the .......... Using hand operated knobs makes this job infinitely easier.
Go to www.astronomy-shoppe.com (http://www.astronomy-shoppe.com) and your prayers will be answered.
Total cost del is about $50AUS. I noticed a very positive difference.:)

[sejanus]

sorry i thought the cheshire was a specific brand of one rather than a description of it. thanks

[sejanus]

by gosh that sounds pretty full on. Doesn't make a huge amount of sense yet but I'm sure it will when the scope arrives, I'll reread this thread when it does. thanks!

Gotta learn to drift align now before it arrives :scared: