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BilliGoatsGruff
02-05-2015, 04:13 PM
I didn't realise that I needed anything to collimate my scope, but after reading the setup book it looks like I do! Does anyone have an idea on how I can do it without having to purchase the equipment to do it?

astroboof
02-05-2015, 05:20 PM
Yep.
1. Grab yourself an empty film canister and cut the bottom off, then drill a small neat hole in the dead center of the canister cap, no more than 1-2mm.
2. Browse yourself some reflector collimation basic how-to's provided by the internet, even this or other forums!
3. Crack a beer afterwards and feel content with a new skill.

Its that easy. :)

astroboof
02-05-2015, 05:24 PM
Oh, you gotta put your newly crafted collimation tool into the focuser.
Then you have to look through it.
Preferably daytime.

Its foolproof.....

BilliGoatsGruff
02-05-2015, 06:11 PM
The catch is, I dont have anything to use. No film canisters, nada.

Hahaha and beer is definitely not my weapon of choice!

barx1963
02-05-2015, 06:24 PM
Billi
First rule of collimation is don't stress about it! With a scope like that, pretty good collimation is all you need. A good guide to basic collimation is here http://www.astro-baby.com/collimation/astro%20babys%20collimation%20guide .htm
The thing with a film canister is that it is used to get your eye centred in the focuser. That is all it does. So get a bit of card, cut out a circle the same size as your focuser tube, punch a hole in the middle, hold it over the end of the focuser and look through the hole. It is not perfect but will enable you to get pretty close with your collimation.

Malcolm

BilliGoatsGruff
02-05-2015, 06:32 PM
Thanks Malcolm! I have heaps of cardboard from the packaging so that should do just nicely :)

doppler
02-05-2015, 08:18 PM
Keep an eye out when you are at the supermarket, 35mm film has a use by date and you can get some cheap canisters then. I use them to plug the focuser holes to keep out dust when storing my scopes.
Rick

MichaelSW
03-05-2015, 10:14 AM
I drop in occasionally to what would have been the Film Processing counter at Pharmacies when going through Shopping Centres. Some still have a supply of empty film canisters under the counter.

Keep in mind that the canisters for some film brands were just a wee bit too wide to fit into the focuser tube.

BeanerSA
03-05-2015, 10:25 AM
My telescope hasn't needed collimation since I got it. Don't do it unless you actually need to. Most small reflectors will never require it.

Jason D
03-05-2015, 03:36 PM
The idea of using a film canister as a collimation cap is an old idea. It was recommended in the past mainly because film canisters were widely available. However, with this age of digital photography I am unsure if it is still a good idea to recommend it -- mainly because it is not as available as it used to be.
There is nothing special about a film canister. Just find any cylindrical bottle that is 1.25" in diameter and it will do the job. For example, here is the USA, Walgreen dispenses medication in plastic bottles that happened to be 1.25" in diameter. Look around your home. Maybe you will find 1.25" pastic cylindrical bottles.
Worse case, just draw bulls-eye circles on a piece of paper then poke a 2mm hole in the middle. Then cut it and tape it to the focuser. Make sure the hole is centered. Now you have one of the cheapest collimation cap equivalence.
Jason

BilliGoatsGruff
03-05-2015, 03:54 PM
Thanks for the help everyone! After feeling defeated last night, I tried again today while my hubby and the kids were out. Hahaha I used the card trick as Malcolm suggested and I think it worked really well. Now just to keep everyone away from the shiney screws that hold the primary mirror in place!
:D

speach
03-05-2015, 05:09 PM
Just buy a laser collimator only a few dollars, and with it it's a 30 sec job.

BilliGoatsGruff
03-05-2015, 05:13 PM
I will eventually.

barx1963
03-05-2015, 10:03 PM
Of course the question here is, how do you know it doesn't need collimation?

Malcolm

BilliGoatsGruff
03-05-2015, 10:22 PM
I didn't see that comment tucked away with all the rest. It honestly had to be done. We accidentally adjusted the primary mirror when I first got the scope (because who reads instructions?) and turned it into a useless piece of equipment. I didn't realise that until I began to collumate it so I'm glad that I did :)

BeanerSA
03-05-2015, 11:01 PM
Every time I'm using the scope, I quickly defocus on a star, and make sure I get a nice even donut shape. That combined with the fact that I have zero complaints about the viewing lead me to believe that the scope is collimated well enough for visual observing. It's a 150mm and my research has lead me to believe that they rarely go out of collimation, but I am prepared for the fact that it may one day.

OneSmallStep
12-05-2015, 06:41 PM
Wait! You can still get film canisters??? Haven't seen one in years.

Speaking of film canisters and beer, anyone here ever play the drinking game with film canisters in their youth? :lol:

kens
12-05-2015, 09:36 PM
You can test it the same way as BeanerSA described. If its not quite right you can fine tune it on the spot