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Hello everbody,

I have a question about collimation.

I'm only using a collimation cap while I collimate.

I like the collimation cap because it very easy and quick to use.

Is this enough or should I (better)use a laser and cheshire also?

I'm only using my scopes for visual observations.

Thanks in advanced

greets Gert

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Hi Gert,

I prefer to just use a collimation cap when collimating my 250PX. I do have a Baader laser collimator, but when I set up the scope with it, and then look through the collimation cap, I don't see all the primary mirror clips equally. A quick tweak of the primary again, using the cap, and all's well. 

I believe that, if, when viewed through the cap, the secondary looks round, all primary clips are visible, and the center spot is bang on you're good to go. You don't need to do anything else.

Kev.

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Posted (edited)

Using just a collimation cap is perfectly acceptable. If done correctly, it is close enough for visual observations.

A cheshire is just a step up from that and is a bit more accurate. A laser can speed things up and is good for fine tuning. It's also much easier to align your primary with a laser if you have a larger scope, like I do, so you don't have to make a small adjustment and then look through the eyepiece every time.

It's not uncommon for me to use a combination of collimation cap and laser and then check them against each other.

Edited by Buzzard75
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I would stick with what your doing if it's working. Star tests will get you the last extra bit of accuracy just as well or better than any other contraption will.

I use a Bbarlowed laser only because my Newtonian is big and it's like doing squat thrusts standing up to the eyepiece then going down to the mirror adjusters and back and forth when using a collimation cap.

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I used a combination of cap and Cheshire for a while and got good results. Moved to a Baader laser recently which is very good and simple to use. Problem you can have with lasers is that sometimes they are not collimated. Also focus slop can show up differences between a laser and a Cheshire or cap, can lead to confusion with the different results. I do use a self centering adapter for collimation which minimises focus slop, and for observing with 1.25 EPs so they are in the same position as the laser was. I find this gives really good accuracy on F5 mirror. As Paz said if its working for you no need to change anything.

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A collimation cap is fine for primary collimation, but I find a laser to be excellent and quick for secondary alignment when needed.  It's super easy to tell when the mirror is square on to the focuser and then aimed at the center of the primary.  The laser is useful for collimating truss dobs' primary mirrors by watching for when the return spot coincides with the outbound spot on the secondary without ever leaving the back of the dob.

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