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What is the best collimator for the money?

collimation Celestron
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#51 Jon Isaacs

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Posted 13 April 2019 - 07:51 AM

Simple thin beam lasers like this are best for aligning the secondary mirror tilt (focuser axis), and if your scope is f/6 or slower, the return beam can be used for primary mirror tilt alignment. At f/5 (or faster), you'll get a better primary mirror alignment with a simple collimation cap (which is relatively insensitive to residual tilt errors in the focuser/adapter/laser). And if you have the simple thin beam laser and the collimation cap, you can do a pretty good job getting the secondary mirror placement sorted (see Jason's procedure here  https://www.cloudyni...ment/?p=5260727

 

:waytogo:

 

Vic's friend Nils Olof Carlin's Barlowed Laser is another option for aligning the primary.  It has the same advantages as the collimation cap but can be easier to read.  I used it for a number of years with my 12.5 inch F/4.06.  When I did get a Tubeblug, it was certainly easier than the Barlowed laser but both were in agreement.

 

http://www.micosmos....lowed_Laser.pdf

 

Jon


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#52 Vic Menard

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Posted 13 April 2019 - 09:20 AM

One benefit of the collimation cap over the Barlowed laser is that the collimation cap allows the user to actually see the secondary mirror placement (especially when combined with a simple thin beam laser). This, of course, is the reason so many beginners are confused when the laser alignment and the collimation cap alignment don't exactly agree...



#53 whizbang

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Posted 13 April 2019 - 11:08 AM

I got an American made Orion Cheshire on the CN Classifieds for $20.

 

Best collimator for the money IMHO.



#54 marcdm

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Posted 16 April 2019 - 09:23 PM

Not the most sophisticated and time will tell if it is effective but here is my answer for a homemade collimation cap.  No film canisters available.  I cruised our local hardware store for a solution and came across a the threaded knob shown below.  It's base is 1.25 inches and the aperture through the threads is about 5mm.  I glued a tight fitting bearing to give me a sight tube but I also thought of filling the cavity with epoxy and drilling a narrower sighting hole.  The goal was to find something as ready made as possible.  Got to blow out that dust!    

                                                                                                                                      Marc

 

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#55 marcdm

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Posted 16 April 2019 - 09:31 PM

Here is a view from the top of the hardware store collimator.  Marc

 

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