mirror lens

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knocker

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Barry
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i have been offered an old tamron f8 mirror lens, it's in good condition and takes a pretty good picture from my quick tests in the chaps garden, static objects seem to be quite sharp even at distance, now, i know nothing about mirror lenses, so, anything i should be aware of please, apart from the obvious manual focus of course ;) and any tips for what uses they have
 
Offered as in given take it

Offered as in pay more than about £20 leave it
 
They are normally Maksutov Cassegrain or Schmidt Cassregrain design lenses, it looks like the Tamron is a Schmidt. The problem is, the objective is too small to allow for the comparatively large objective central obstruction. As the objective gets larger, the obstruction becomes proportionately smaller, compared to the area of the objective. The obstruction affects image contrast.

There's more info here on the specifics of the Tamron.

A 90mm objective Mak make's a pretty good small telescopes. I have a Mak with a 102mm diameter obejective and it's actually pretty good, I've posted some of the moon shots I've taken. It is however f13, so pretty slow....
 
Manual focus, fixed aperture, generally poor IQ.
At least that's how I've always found mirror lenses. Not recommended honestly, unless it's dirt cheap and you just want to play around with one.
 
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