Quote:
Originally Posted by shelltree
I was actually talking to Suzy the other night about this and she said dew does become a problem on the Telrad. I have used one before and found it very easy to find bright objects at least. I don't think I could find things with just the Telrad alone, I need my star hops! A straight finder makes it difficult though, the ol' neck gets sore very easily.
StarMap Pro actually has a setting for Telrad which would be very handy, it shows the circles and changes as you zoom in. All in time though...when I have money  |
Yes, the basic Telrad is very dew prone. I bought flip-up dew caps for my three Telrads, and they delayed the onset of dew by about 5 minutes. Then I stuck aluminium foil all over them with Blutack ( a suggestion from Sky & Telescope), and that delayed the onset of dew by about 20 minutes on bad nights, or an hour on not so bad nights - before I had to apply a blower.
The other thing I experimented with was using 3X and 8X and 10X binoculars behind the Telrad - and that worked really well - but it was also superfluous when I already had correct image 8X50 finder scopes.
The red dot finders are less expensive on Ebay, and I picked up a good second hand one here for $15. I can stick them onto telescopes with that double sided sticky thing used to stick things on walls. And with some tape and plastic from a cheap folder, it's easy to fashion a long dew shield for them.
Your neck will be a lot less sore even when using a straight through finder, as you won't have to muck around as much with the straight through finder.
Only problem with red dot finders is that they have a variety of bases - some with flat bit designed to be screwed into the telescope (the sticky stuff works great with them) to those made to slide into mounting brackets.
Cheers,
Renato