Unitron eyepieces + telescope question

[ralph1]

Hi all, I have two unitron kellners, a 25mm and 12.5mm in 0.965 inch barrels and I want to know if it is worth getting an adaptor to use them in my current telescope and future one I am building. I currently own a 6mm orion edge on, a 15mm celestron kellner and a bintel 30mm superview. The current telescope is a 130mm F/5 and the one I'm building will be a 175mm F/13.

I also have a refractor with 'topic astronomical telescope' on the nameplate(I don't know the technical name) and google wouldn't reveal any information on it. If anyone knows about this telescope, their knowledge would be appreciated. i.e. optical quality, mechanical quality etc. It is a 60mm F/15
Thanks, Ralph

[Tropo-Bob (Bob)]

The Unitron Kellners work best at longer F ratios. However, they have a small field of view (aprox 37-40 degrees) by the standard of eyepieces available these days. A adapter does not cost much, but then again, I do not think that these eyepieces will be of much use either.

I have a 25mm Unitron Kellner and have oddly found that the best use for it is as a low powered microscope (or high powered magnifying glass) when viewing small objects by 'reverse' viewing though the eyepiece.

A final word of caution: I once ruined a very good star diagonal by dropping an 1 inch eyepiece into it (in the dark) and forgetting the adaptor. It cracked the mirror of the star diagonal. Sad really, and costly.