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Mak frustrations! "the sequel"


Guest recceranger
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Guest recceranger

Having previously placed a post asking for advice on my Mak and its below power performance the other night I went through a series of collimation tests as advised by experts.  Collimation was off and needed correcting.  Two methods were suggested, both indoors and although tricky I had to have a bash (it needed sorting).  


 


Well, my bash was totally unsuccessful i.e. a complete fail.  To make matters worse, I made matters worse!  I have been chasing error with a set of tools for the last 2 - 3 hours.


 


Its apparent that I need a skilled hand to carry out the task.  Does anyone know where I can get this done, sooner rather than later?  I'm willing to send it off as at the moment its about as much use as a chocolate fire guard!


 


I really want to get it up and running as once on power its the business end for catching planets.


 


Help and advice sought and appreciated


 


Rick


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Bad luck Richard but I did warn you not to touch the collimation, for a very good reason, they are sods to get right.


 


What daytime collimation test and adjustment did you perform, and more importantly where did you get the advice?

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Guest recceranger


Phil,


 


You did indeed mate.  Having said that, it was out and enough that it required adjustment.  The source of info came via the Orion Mak 180 Pro instructions that I downloaded direct from the company.  Involves looking through the back visual and carrying out real time adjustments.  But its a real melodrama!  In short, the adjustment screws move the main mirror via push and pull which is easy if your a Jedi Knight!


 


I'm just a green amateur so its all went south.  On the plus side I didn't take it apart (scant conciliation I know).  


 


The other method was via observation of ring pattern on the main lens from the front.  Adjustment was then carried out.  This is easier and the method I used to get it back to some semblance of a basic bore sighting.  But its off and off its likely to remain until I find a Mak user/retailer who knows what he/she is doing.

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Using a colli cap or even a cheshire will help. Make sure its held central in the visual back and doesnt wobble,. Then look through. Concentric circles is what your after. If its out the circles will be off. Adjust a push pull screw in a small amount then look what its done, if its made it worse then go the oppossite way etc etc.

Doing the front viewing is too hit and miss for fine collimation but can get you nearish but you need to view it from the same position each time, use a pin hole viewer otherwise your chasing your tail. I dont recommend this method

once youve got it near then final adjustments are done on a still clear night on a star. Get the star central and check the out of focus image with a highish mag eyepiece again you are after concentric circles, adjust in even smaller amounts until perfect then lock down.

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Guest recceranger


Thanks Phil,


 


A collimator/cheshire cap?  Is this similar to the farpoint kit etc?  


 


The push/pull screws are the true drama as they send the Con Circles off on a Crazy Ivan!  If I get the correct kit Im in business.


 


Many thanks for the advice and this time I WILL LISTEN!!!!!!


 


Rick


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Do all collimation without diagonals in. You are trying to remove all possibilities of false readings from other kit. Get the scope collimated 1st. Then put a diagonal in and check, if things then look out your disgonal is causing you problems

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Please do not think that Maks need collimating as a matter of course. They do not. They should hold their collimation from the factory for ever more. You only need to think of collimation if youve dropped it, fiddled with it or a previous owner has faffed about with it.

My advice Phil is not to get caught up in thinking about collimation. If you want to test on a star then by all means but do not, repeat do not even think of adjusting if its not necessary.

to star test any scope, let the scope cool for a good hour on a still and clear night. Point the scope at a star. Take the diagonal off and just use a medium mag ep direct into the scope. Focus and make sure the star is in the middle. Now defocus, you will get a perfect doughnut with a well collimated mak scope.

The most important do not be tempted to twiddle or fiddle if things look a little off centre. Investigate all possibilies for the cause, it wont necessarily be the scope.

You have been warned

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Thanks for reply all

I am sending off to Kay Optical Repairs and they will reset the bugger. It's a Jedi Knight skill!

I will send a bit of a review when I get it back and star test.

Rick

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Guest CodnorPaul

Forgive the newbie here but if you star test with diagonal in and get it collimated then is that not better as that is how you would use it, therefore your optical system is in sync? Have I missed something or done it wrong? Then if doing AP it is without so that is how you would collimate?


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Yes you can do that but if your diagonal is out then what happens when you remove the diagonal and swap it for another accessory or even a camera? The view will be off. Or if your diagonal is off and you rotate it away from the position when you collimated the scope/diag set up then you have problems.

Always collimate the scope on its own, you will then know the scope is right thus if you fit anything else in the optical train and its off then you know its not the scope but the thing youve fitted.

Yes diagonals can be out of collimation. The old Tal diagonals had collimation screws on the back just for this purpose.

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