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Old 26-10-2017, 04:36 PM
Astromelb
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Takahashi CN212 Newtonian Cassegrain Reflecting telescope - PRICE REDUCED

FOR SALE - Takahashi CN212 Newtonian Cassegrain Reflecting telescope

This is a unique scope which comes with both a Cassegrain operation using a Cassegrain secondary.
Plus also a Newtonian operational capability, using a Newtonian seconday mirror. Thereby giving you two telescopes in one

You can change the secondary in a few short minutes to change the format to either a Cassegrain for visual or a fast Newtonian format for imaging.

This scope is one of a kind. It is also no longer manufactured

The optical principle of the CN-212 is simple yet clever. From a primary short focus parabolic mirror, pierced centrally, different optical configurations are possible depending on the secondary mirror placed in the light cone. Here we have two telescopes in one, an f/12.4 Cassegrain as the basic configuration, with a hyperbolic secondary mirror for high resolution work, or when you require, by simply replacing the secondary mirror and coupled with a low profile 2" eyepeice adaptor and associated field corrector, you transform your instrument into a brilliant wide field Newtonian with a focal ratio of f/3.9.

Excellent condition, I bought this telescope from Matt S (Kunama) nearly a year ago and straight after bought an Officina Stellare Supremo Mak 280mm - the world's best full Carbon tubed with Sitall optics and a Strehl of 0.99 Cass - this CN212 unit has been used once, it deserves a new home with someone that will actually use it. Matt takes exceptional care of his gear and this unit suits new buyer

Pick up in Melbourne

Thanks for looking
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Last edited by Astromelb; 13-11-2017 at 07:41 AM. Reason: PRICE REDUCED
  #2  
Old 27-10-2017, 06:33 PM
thebonz (John)
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cn photos

Show me the photos
  #3  
Old 29-10-2017, 09:04 PM
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dave brock
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I assume the CN212 means it's 212mm diameter?

Dave
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Old 10-11-2017, 08:21 PM
thebonz (John)
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cn212

I have a specific interest in the Newtonian focusing. Does the current configuration involve adjusting the primary mirror and if so does this effect the final collimation.
  #5  
Old 11-11-2017, 08:24 AM
Astromelb
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Dear John (thebonz),

Thank you for your enquiry.
The system has two separate precision made Takahashi assemblies that attach to the spider and enable either a Cassegrain operation, or with the separate assembly a Newtonian operation.

The Newtonian process then fits up the included Takahashi focuser that attaches to the recess on the side of the OTA near the top where the black plastic plug is located in the pics.

The assemblies that fit into the spider are very cleverly sleeved and edge profiled - so that they only fit correctly every time and only in one configuration and attach with a simple tensioning screw.

There is no need for recollimation, as once set and with the clever design that Takahashi have utilised for this design you can change from Newtonian to Cassegrain or the other way around in just a few minutes and do not need to recollimate, as having correct collimation the system in the first place the alignment is retained.

There is no adjustment to the collimation on the primary mirror required.

Trust this assists.

Last edited by Astromelb; 11-11-2017 at 11:42 AM.
  #6  
Old 13-11-2017, 07:38 AM
Astromelb
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Withdrawing the unit, if anyone has any interest they are welcome to contact me if they are interested. With thanks.
 

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