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Collimation service for quad?

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#1 Cerberus



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Posted 14 October 2019 - 02:55 AM

I have a 71mm SDQ quadruplet with 3 element objective that I manage to mess up trying to fix an issue that turned out to be with the filter wheel and not the scope itself. Is there a shop or lab that I can send my scope to recenter my lens elements?

Right now its showing noticeable coma and CA evenly across the field. I've fixed doublet ED and achro scopes, but doing 3 elements is beyond my skill and patience.



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Posted 14 October 2019 - 03:17 AM

Yeah, that's like dismembering a transmission with one set of open-end wrenches... and then hoping to put humpty back together again.


Heh! At work, I was attached to the Optical Metrology group... where we did the alignments on complex imaging satellites and myriad other things. By far, the most common walk-in service we provided was stuff from the production floor that had gotten knocked out of kilter. And among those, the most common scenario was where some tech, engineer or scientist said the gizmo "just spontaneously stopped functioning properly". Then, sure enough... we'd get to working on it and find flipped elements, finger prints, etc. etc. all over the place. And the (company-internal) customer would insist they had never touched it.


I'll bet vendors and manufacturers get returned "defective" telescopes all the time --- that, obviously have been dismembered by customers.


Why not just send it to the dealer you bought it from, with an explanation of what happened? I'm sure they will fix it, for a nominal fee. It will take an interferometer and/or  Axicon Autocollimator to get it right. Full-service repair shops have those and the skills to use them. The shop that built it --- that exact make and model --- will have the same tools they used to assemble it!   Tom

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#3 25585



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Posted 14 October 2019 - 10:38 AM

I have turned down pre-owned Petzvals, because of fear they might be mis-collimated. Reading on CN of NP101s being bought new and out of collimation, & hassles getting them put right.


Its a reason for my buying new a TSA120 triplet by Takahashi, surety of perfect condition and collimation from the start.  

#4 Element79


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Posted 14 October 2019 - 10:47 AM

Company Seven can recollimate the lenses.

#5 Eric H

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Posted 14 October 2019 - 10:47 AM

Try Mike @ http://www.axissquared.com/. Not sure he can help but maybe he can lead you to the best source.


He's also a vendor here.

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