Collimating my 200p (possibly going horribly wrong!)

[benjii]

Well my new Skyliner 200p arrived yesterday from FLO, very fast service I might add!

Skys look clear for tonight, so I set about attempting to collimate my first telescope. Looking down a chesire it looks like the example pictures you get to see how badly telescopes can be collimated, the crosshairs were all in the bottom left corner, nothing was lined up. The secondary mirror was horribly off centre too; this is the last thing I wanted!

I'm trying my best to follow Astro Baby's guide, so far my secondary mirror looks like this:

As you can see, there's more of a gap to the left and bottom than elsewhere. How important is it for it to be perfectly centred? Any help would be greatly appreciated. Thanks.

[Zachariah]

I have just had a skyliner 150 and accirding to my laser its off too. I do really think suppliers should check and adjust before despatch.

[littlebeagle]

To be honest for my first few nights I'd be quite happy with my secondary if it was like that, mine is off centre slightly at the moment and I got fantastic views of Jupiter the other night.

[Parus major]

I have just had a skyliner 150 and accirding to my laser its off too. I do really think suppliers should check and adjust before despatch.

I wouldn't matter if they did since you can knock an F5 out of collimation by putting it in the car for twenty minutes and these things get made in China.

Astro Babys Guide to Collimation

[benjii]

I can't seem to get it all perfectly lined up. I had 3 mirror clips in view and the black dot and the primary mirror ring perfectly lined up with it. They were along the horizontal crosshair line of the chesire, but just a little too far to the right of the vertical line. Now it looks something like this(I lost the third clip):

When I get the third clip back, how do I move the black dot, which I assume is the secondary mirror to the crosshair of the chesire without screwing it all up?

[Tinker1947]

Get the mirror clips lined up, by useing a cap with the hole in the centre, then adjust the secondary mirror so the paper clip in dead center using the cross hair in the Cheshire, disregard any thing else you see through the Cheshire, once this is done adjust the primary useing the angles reflector on Cheshire. I had a SW 10" Reflector from FLO, never needed collimating untill i flocked the tube some 3 months later...

[Parus major]

I think in the 200 you can't see all the primary clips so tweek it so they're all on the edge of visible. the center dot is moved by the primary.

Seconday gets the clips, primary moves the center dot ring.

[benjii]

Thank you all for your help, I'll keep trying! Parus, sorry if I didn't explain myself clearly enough! What I was trying to say was, according to Astro Baby's guide, you need to line up the black dot, with the ring from the primary mirror, then have the crosshair intersect them. It's the black dot I can't move properly.

[umadog]

You iterate back and forth between both adjustments until they're right. To a degree, this is a mechanical skill. Turn the primary adjustment screws by small increments and observe the results. Eventually you'll get super-good at knowing which screw to turn and by how much. You can do the adjustment as easily with two screws as with all three. If you restrict yourself to two of the screws (doesn't matter which ones) you may pick things up quicker as you're simplifying the problem.

[insomnia]

You are lucky getting any clips in view. I did a first time collimation a few days ago and I can not get any clips to show.

[kniclander]

no clips might be ok - it might just be that the secondary is slightly undersized or the focusser is racked too far out. having some clips showing but not others is not good - it means the secondary is not lined up properly (I think....).

[benjii]

I managed it, at last! Incase it helps others, I'll share some things I picked up.

First off, Astro Babys guide is very good, definitely follow that to the letter. Umadog has a very good point, I found it easiest to get it almost perfect with using only 2 screws, then use the third to just tweak it. With a chesire, you can only just get all 3 mirror clips in view with a 200p, they're more like faint lines then the blocks everyone seems to talk about. Lastly, if you're having issues lining up the secondary mirror dot with with primiary mirror ring dot, go back to the 3 clips and lining those up, as that's probably where the issue lies.

[littlebeagle]

kniclander makes a very good point, it's easier to align the secondary with the focuser most the way out but then you usually can't see the clips so it's easier to put the focuser in for that bit.

[Thirdway]

This all sounds a bit scary. I have a Cheshire and a Skywatcher 8" Dob on the way from FLO. I'm pretty good mechanically so thought this would be easy.....hmm sounds more complex than first thought. Mind you, setting up drum heads is a bit of an art.

[tone71]

Looks too scary for me to

Havent even thought about doing mine yet, dont want to open the can of wrigglys

[todd8137]

i can not had nothing to what as already been said ,apart from asto babys pics gave me what i needed it could not have been simpler ,getting everything in her pics the same took me about 20 goes ,18 paracetamol ,and about 6 hours now its easy thanks to those straight to the point pics on her guide

[Thirdway]

I have flashbacks to setting up my sub woofer and parametric equaliser. Hours of hand drawn graphs, measurements and tiny incremental programme changes to each of the hundreds of frequency bands of the equaliser. I still have nightmares about it. After careful setting up I changed to another room and just can't go through it again. Oh the pain.