Collimation for beginners...another link

davidpretorius · #1 19-08-2005, 08:59 AM

Hi all,

It was raining, i meditated for 20 minutes and took the plunge........screwdriver in hand, i nervously took the screws of the bottom of the tube and took out the primary mirror. Put the whole lot on some speaker foam i had bought form jaycar, covered it with a towel, sat down and waited for my nerves to settle!!!!

...20 mins later... out came the mirror and now is proudly sitting there waiting to be centre spotted. jumped on the internet to read the collimation article in the projects section, but the site was down.....bugga....

so i did a search on the internet and found this rather good link. http://www.schlatter.org/Dad/Astronomy/collimate.htm

called collimating my dob.

a great read for any dob owner.

With the rain continuing, i will be having a go at this tonight. Asimov will tell me "Good Boy"! "Stop being such a woos"

by the way, just checking, the screws with springs are for adjusting, the ones with out springs are for locking???

slice of heaven · #2 19-08-2005, 09:41 AM

The 3 screws without springs are the push screws and the 3 with springs are the pull screws. 6 screws make for an awkward adjusting process. I replaced the springs on my 12 with heavier ss springs and have no need for the 3 push screws.

Thiink · #3 19-08-2005, 12:42 PM

I wouldn't mind getting rid of the three locking screws (well, I thought they were locking screws!). Where did you get the springs from? I always seem to knock my collimation out when I adjust the "locking" screws up.

iceman (Mike) · #4 19-08-2005, 01:02 PM

I never touch the locking screws, they're loose and I don't use them. I found they didn't help to keep the scope collimated.. it stays in collimation mostly on it's own.

I check collimation before each imaging session, or after transporting to a dark site and back, and it never requires much more than half a tweak on one of the screws to get the dot back to the centre.

elusiver · #5 19-08-2005, 01:20 PM

i'm like mike.. and leave the locking screw loose.

el

rmcpb (Rob) · #6 19-08-2005, 01:38 PM

I don't use the locking screws. Apart from not helping keep the scope in collimation I find them a nuisance as they tend to change the setting when you are tightening them up.

slice of heaven · #7 19-08-2005, 02:22 PM

Quote:

Originally Posted by Thiink

I wouldn't mind getting rid of the three locking screws (well, I thought they were locking screws!). Where did you get the springs from? I always seem to knock my collimation out when I adjust the "locking" screws up.

I got the springs from a local engineering firm. I used coated springs till the ss springs came in. For a quick fix you can tighten the 3 screws with springs to compress the springs to make it more rigid,and recollimate from there.

asimov (John) · #8 19-08-2005, 02:51 PM

I always nip my locking screws up. Does'nt affect my collimation one little bit. I've never seen a GS primary cell though...perhaps their a different setup than Parks.

No need to centre spot my primary either. No cheshire.

Starkler (Geoff) · #9 19-08-2005, 05:03 PM

On locking screws

http://www.iceinspace.com.au/forum/s...ead.php?t=2486

asimov (John) · #10 19-08-2005, 05:10 PM

See? I took your advice from back then geoffro!

asimov (John) · #11 19-08-2005, 06:55 PM

I still like to do as slice suggested, no matter what.

As Geoff suggests, If you do those locking screws up in increments, & in order & keep checking your collimation one should'nt have much trouble.