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Dilworth, not Cassegrain

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Xilman's picture
Last seen: 5 hours 57 min ago
Joined: 24/03/2018 - 15:17
Dilworth, not Cassegrain

When I purchased Tacande observatory a year ago, the information pack included the text:

Professional 400 mm. telescope: Exceptional optical quality, recommended for Deep Sky, planetary or lunar observations. Prototype of the Cassegrain-Relay type optical system. Manufactured by the Swiss company Larrosa Precision Optics. Please see...

and so I've been calling it a Cassegrain ever since.
A couple of days ago Victor Larrosa mailed me to explain that it is not a Cassegrain, but a Dilworth.  He also told me that all the optical surfaces (apart from the plane window enclosing the tube) were spherical and provided a design drawing of the optical arrangement.
Accordingly it will be described as a Dilworth-Relay telescope from now on. Regardless of the name, it's an excellent piece of kit.
Please apply Hanlon's razor.  I'd never heard of the Dilworth design and there seems to be very little information about it on the net.