Collimator Help

[Betelgeux]

Hello,

It was only until recently, at a Star Party, I was told this problem was more serious than I first thought.

Ever since I bought the 'Next Generation laser collimator' http://www.skyatnightmagazine.com/review/miscellaneous/next-generation-laser-collimator when I rotate it in the focuser/eyepiece holder the red dot descibes a circle. I botched a thing to test it and at a distance of about 10' it descibed a circle of around 2". I have heard to remedy this issue to adjust the grub screws on the collimator but found they were sealed (as mentioned in the review link above). It hasn't had any big knocks or falls and has always been stored in its origanal box.

Please can somene advise me.

Thank you in advance.

Betelgeux.

[malc-c]

Can you not remove the seals to get at the set screws ?

If not then the only alternative is to return it to the retailer for replacement / refund and purchase one that allows the laser to be colimated

[Tinker1947]

You will need to adjust it or take it back, i can't think of any other alternative....i use a Baader Mk3 its never been adjusted by my and is steady at 12', but it had the option to adjust.....

[brantuk]

I had one of those "Next Generation" collimators - heap of junk - I had to write it off cos I wouldn't even sell it to a fellow astronomer. Scrap it and go for a Baader (as above) or Hotech like I did - at least they are collimatable.

[cotterless45]

Yep, did the same. The Baader is spot on at 20 feet.

[Betelgeux]

Thank you for your advice. As a new member I am grateful for (and impressed by) your friendly and rapid responses.

I have telephoned the supplier and they have said they will exchange/repair it for a new one.

[brantuk]

Excellent - nice result

[brucen]

I hope your replacement is accurate. I dug out the seals on mine (it came with a sheet saying I might have to) and adjusted it using a stand I made up from plastic plumbing joints. It is now accurate at 15 feet although it did take some time to get it right.

[Moonshane]

hi there

was it you that I spoke with at the weekend? (I was mid swap of focusers on my dobs). hope you get a replacement that works well. personally I prefer a Cheshire but if you want to continue with a lazer I would certainly recommend the barlowed lazer method we discussed. this article http://www.smartavtweaks.com/RVBL.html gives a good representation of what you'll see. this can only do the primary though. for the secondary you really do need a sight tube/Cheshire in my opinion.

not sure where you are in NW England but if close enough to Stockport send me a PM and I'd be glad to try and help.

[Betelgeux]

Yes, it's me from the PSP. I'll see how the replacement goes and if I get the same trouble I'll look into getting a Cheshire.

Stockport is a bit far away from me here in Cheshire but thank you for the offer.

[Betelgeux]

The replacement works perfectly. I must commend the MC2 telescope shop in Frome for exchanging it quickly and easily despite it being such a long time from purchasing.

Thanks for all your help.

[Gomtuu]

Don't chuck it away. It's not completely useless. I use mine (same crappy make) with a Barlow (as in Moonshane's link).

[Betelgeux]

I haven't thrown it away Gomtuu. MC2 helpfully replaced the dodgy one with a new one free of charge. So all's well, that ends well.