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Old 09-01-2020, 06:31 AM
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mental4astro (Alexander)
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mental4astro is offline
 
Join Date: Jun 2008
Location: sydney, australia
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Martin et al,

I'm not a newbie, but on reflection on my own experiences over the years with your question, I hope to allay some fears people may have about refractors vs reflectors (of whatever type).

I have come to see that there are two main reasons for why people take up refractors over Newtonians (or any other type of reflector such as SCT or Mak) when they start out in astro:

* the word "collimation"

* a Newtonian "does not look like a telescope".

Collimation ONLY MEANS aligning the optics. That's it. Nothing more. And sadly seeing all the weird diagrams, gizmos and even lasers to do with collimating, and people become fearful of Newts and cassergrains

That Newts don't look like a telescope stems from most people's only association with any form of telescope is a refractor, yes, that pirates use! Sadly many people's initial knowledge of astronomy and telescopes is entirely set on what pirate's use, and that the gear that professional astronomers use is somehow tantamount to unfathomable "rocket science"... Heck, I even had the Spooks called on me a few years back when setting up a truss dob, and another time a fellow became very pissed off & aggressive with me when he refused to believe that the 5" SCT was showing him Saturn...

I see the confusion and scepticism in many novices at outreach events when they see my Newts or cassegrains as being telescopes instead of a refractor. Not helping the situation for dobs is the odd looking mount instead of a tripod and rocket science equatorial mount. I've also encountered this ignorance when organizing outreach events when the non-astro people I had to work with thought that the scopes we were bringing were hand-held "priate" style telescopes - I kid you not! In one instance these were National Parks rangers



As Carlton said, there really is nothing mysterious or rocket-science about "collimation". It is only tweaking a couple of mirrors to optimise the effectiveness of the scope, it only takes moments, and if you take the time you will get the scope humming at its very best for you with a larger aperture than a refractor can offer for the same price. What refractors do have over reflectors is they typically don't require tweaking of the optics. The inconvenience that some people perceive that the collimation process introduces or the optical artifacts that reflectors can introduce to the image is a factor, but less so.

As for Newtonians and cassegrains (both solid tube and truss designs) not looking like a telescope, I reckon by now your thinking would have changed.

Alex.
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Last edited by mental4astro; 09-01-2020 at 07:59 AM.
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