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Can you tell if this is collimated?


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I collimated using the laser collimator and took this picture, it's the view with no eyepiece in. I had to brighten up the picture so you can see it better. The whole collimation thing scares me a bit and I had already collimated it wthout knowing that the laser has to be collimated too! Nightmare.

I've since bought a cheshire collimator too since the whole collimating the laser thing has put me off them a bit. I'm not even sure if you can tell if it's collimated by this pic but any advice you can offer should make things a bit clearer for me.

I do hope it's not too far out as there is clear skies forecast for this evening. It will be my first adventure outside into the night with my new scope :)

Thanks for your help, without this place I wouldn't have even bought a scope. You really are my haven.

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Hi Geo, that looks good to me. I had a 10" SW, and recall mine had 6 mirror

clips, and I can see most of them in the reflection, close to the edge, and

the 'doughnut' looks central in the middle too.

Maybe a final check on a slightly defocused star perhaps ?

Hope you have a nice observing session, Ed.

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I'm by no means an expert, barely an amateur, but looks ok to me?

Someone once told me that if you have to do it manually, remove eye piece, and point the scope at something bright indoors.

Look through focuser.

If you see your eye staring back at you, pretty much central, your as good as you can get without a laser.

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It looks good to me as well. You can see most of the clips, the secondary looks circular and you can see the off set. The donut looks central as well. Just do a star test but I think it's pretty close.

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It should look like the image in the top right of the watermarks on this PDF:

http://homepage.mac.com/vicmenard/telescopes/NPaddendbook.pdf

You're nearly there!

The primary isn't in the centre of the secondary. See how in the diagram the edge of the primary is concentric with edge of the secondary. Also note that in the diagram, the reflection of the centre spot is not in the centre of the secondary. That is the way things should be when you're properly collimated. I think your photo shows that this isn't the case with your scope (but I haven't measured your image, so I might be wrong). I don't have the have the experience to tell you why this isn't the case, but hopefully someone with more experience will chime in. I found I could get it properly collimated by following these instructions:

John Reed Home Page Collimation - Cheshire

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The laser collimator HAS to be collimated too? I have to admit that collimation scares the hell out of me too and am waiting for my collimator to arrive by mail,..

I'll soon take the plunge and will probably be posting a picture like yours when finished (just to make sure).

Isabelle

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Yep. Cheaper laser collimators need to be collimated. This can make your life harder rather than easier, unless you keep an eye on it. One advantage of going the cheshire/autocollimator route is that you don't need to worry about collimating the tools. In addition, the autocollimator is super accurate.

Don't let collimation scare you, though. It's not so hard and you can't damage the scope unless you do something really silly.

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  • 7 months later...

Hi Geo,i was the same i only got the scope and read about collimated i didn't know if it was already done or i had to do it but a few replys back saying it should be fine straight out of box,,John Denim quoted if you see your eye looking back it's fine and thats the way my scope is,,i haven't gone outside yet has been a bit cloudy overhead so just waiting on a clear sky to try and see whats out there,,the 2 EP's that came with mine is 10mm,20mm (celestron 130eq) are they any good,,I'm new to all this so i may from time 2 time be asking lots of ??'s greg

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if you see your eye looking back it's fine a

I'm afraid seeing you eye's reflection does not mean it's collimated. There are many situations under which you can see the eye's reflection and have the scope out of collimation. Most people find they need to tweak the collimation each time they view. Although this is less likely with smaller, solid-tube, scopes. It's very unlikely the scope is accurately collimated out of the box, although it may well be passable out of the box.

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The first time is the worst, especially if the secondary is out. But once the secondary is done, it'l hold collimation pretty well unless you drop it down the stairs or use it as a novelty baseball bat. Usually you just need to tweak the primary, which is a 2 minute job and much easier than a full collimation.

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don't be afraid of collimation just have a go and try to understand each stage and what you are actually doing, with practice you will get as good with just your eye as any other method, for speed though I like to use a cheshire its all the tool you need, for centering the secondary and adjusting primary. The laser is ok for quick check but make sure its true also.

The laser is not as accurate as the cheshire in may opinion. star test on a steady night is the final test.

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