How to collimate SkyWatcher 130p

BilliGoatsGruff (Billi) · #1 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 (Steve McN) · #2 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 (Steve McN) · #3 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 (Billi) · #4 02-05-2015, 06:11 PM

Quote:

Originally Posted by astroboof

Oh, you gotta put your newly crafted collimation tool into the focuser.
Then you have to look through it.
Preferably daytime.

Its foolproof.....

The catch is, I dont have anything to use. No film canisters, nada.

Hahaha and beer is definitely not my weapon of choice!

barx1963 (Malcolm) · #5 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/collimatio...on%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 (Billi) · #6 02-05-2015, 06:32 PM

Quote:

Originally Posted by barx1963

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/collimatio...on%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

Thanks Malcolm! I have heaps of cardboard from the packaging so that should do just nicely

doppler (Rick) · #7 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 (Michael) · #8 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 (Paul) · #9 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 (Jason) · #10 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 (Billi) · #11 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!

speach (Simon) · #12 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 (Billi) · #13 03-05-2015, 05:13 PM

I will eventually.

barx1963 (Malcolm) · #14 03-05-2015, 10:03 PM

Quote:

Originally Posted by BeanerSA

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.

Of course the question here is, how do you know it doesn't need collimation?

Malcolm

BilliGoatsGruff (Billi) · #15 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 (Paul) · #16 03-05-2015, 11:01 PM

Quote:

Originally Posted by barx1963

Of course the question here is, how do you know it doesn't need collimation?

Malcolm

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 (Australia) · #17 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?

kens (Ken) · #18 12-05-2015, 09:36 PM

Quote:

Originally Posted by BilliGoatsGruff

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!

You can test it the same way as BeanerSA described. If its not quite right you can fine tune it on the spot