Skywatcher 250px Collimation Confusion

[Crimson Sunset]

Hi all.

My 250px arrived today but i've had an awful lot of trouble trying to collimate it, in particular getting the secondary mirror aligned with the primary (it was fairly out of whack from the get go). I've been using astrobaby's guide along with several others but don't seem to understand. In most diagrams, there are three primary clips which need to be shown on the secondary, but in the 250px there are 6 clips which seem physically impossible to fit into the same field of view (with either a homemade film canister collimation cap or with my cheshire).

I spent two hours trying to the scope into some kind of useful state, but to no avail. Hopefully somebody here can point me in the right direction!

Cameron

[Tinker1947]

I 'm not sure you will get all the primary clips in view, just get them so the ones you see are all equal, i think this part is to ensure the secondary is in the right place opposite the focuses tube, the next thing would be to use the cheshire cross wire to aligne the paper circle in the centre, useing the secondary adjusters, after this use the primary adjusters to align using the cheshire by looking at the shiny angled reflector. Well thats how i think i done mine and and on a star test it showed a perfect spiders web when taken right out of focus. So if its not how it should be done, somebody will type the correct way..

[Toast]

I had the same problem with my 200p, and it turns out you don't need to see the 3 primary clips. Instead, line up the donut that's on the primary with the crosshair in your cheshire. This will achieve the same thing. Once alligned, you can then move onto the final step of adjusting the primary.

This guide helped me the most: John Reed Home Page Collimation - Cheshire

[Crimson Sunset]

Thanks so much both of you, that seems a lot simpler.

I'll give it a try and hopefully won't take as long today, I probably should have asked here first before wasting two hours on it!

Edit: Fantastic! Twenty minutes and thats it, job done. Good work SGL:icon_salut:

[Javert]

I've just got round to checking mine (scope arrived last Tuesday - an Explorer 200P) and it was quite a bit out.

Have followed Astro Baby's guide but could only see 1 of the clips on the primary. After adjustment I couldn't see any of the clips but I've managed to get pretty much everything in line. I was quite daunted to begin with, but now I feel much more confident in carrying out this process. Ok, I've not got it perfect but it'll do me for now until I get into it.

[Tinker1947]

Practice makes perfect.....