Feel like I'm losing my astro knowledge!!!

[shelltree (Shelley)]

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

[Renato1 (Renato)]

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

[barx1963 (Malcolm)]

I have a cheap Bintel red dot finder on my 8". As it is all set up with Sky Vectors DSC's it really only get used for alignment. But it is subject to dewing. I have found the easy solution is a Click Lock Glad bag, just slip it over when I have done the alignment and if I need he RDF again it is dew free.

Malcolm

[Suzy]

Originally Posted by barx1963

I have a cheap Bintel red dot finder on my 8". As it is all set up with Sky Vectors DSC's it really only get used for alignment. But it is subject to dewing. I have found the easy solution is a Click Lock Glad bag, just slip it over when I have done the alignment and if I need he RDF again it is dew free.

Malcolm

Malcolm that is a super idea!
It's interesting what you said about your cheap RDF dewing. I spent around $70 on mine and it's the last thing to get affected- well after my scope. I hadn't realised there would be such a big difference in quality regarding dew, wow! I will use your idea on my Stellarview finder .

Shell, come back out to my place and we'll fire up my Argo Narvis and have a lots of fun touring . And we'll pass the night away amongst lots of astro chick giggles like we do

Every season, I still have to re-aquaint myself with the sky. Go slow and stick to favourites and add slowly is probably the best advice I can give for remembering where stuff is. And I often stay within a constellation & explore it- it's fun & it puts what I saw into memory better, added to the fact it personalises it more.
An RDF pointing exactly where the object helps too .

Remember when the star, Formalhault surprised me (low-ish on the horizon) with it's return when you were over last time? It's because it's one of my favourites. So I know the return of that star is a sign post of the Sculptor galaxies, Cetus, Phoenix etc. There's no hurry- the sky isn't going anywhere and let's face it- how many people know every constellation up there .
I.M.O if you learn the 26 brightest stars, it will give you more power .
http://www.astro.wisc.edu/~dolan/con...brightest.html

[Suzy]

Hi Renato, I'm really enjoying your input experience in this thread. It's also interesting what you said about the dew caps on the Telrad (I had one with a cap) and I always thought it was because I didn't put the cap on quick enough that it dewed up so much. Now I know I'm not crazy! I got rid of it, I spent more time looking at dew drops .

[astroron (Ron)]

All I do is stick some tissue in my telrad and it is clean as a whistle when time to use it, which is not very often.
Cheers

[Renato1 (Renato)]

Originally Posted by Suzy

Hi Renato, I'm really enjoying your input experience in this thread. It's also interesting what you said about the dew caps on the Telrad (I had one with a cap) and I always thought it was because I didn't put the cap on quick enough that it dewed up so much. Now I know I'm not crazy! I got rid of it, I spent more time looking at dew drops .

Hi Suzy,
Yes, I was extremely disappointed with my flip Telrad dew caps when I got them - though I have seen other longer ones sliding over the whole top of the unit since, which I suspect would do a better job, though they'd be trickier to clean with a tissue when they finally did dew over.

Sticking aluminium foil over the Telrad and dew cap definitely improved things - and that also works on the finderscope dew caps I fashioned from plastic.

A lot also depends on where you live. The aluminium foil trick certainly worked where I used to live in suburbia and at my rural dark site. But since moving to my current location near the bay and next to a gully with a small creek running through it, it still works, but not as well as it used to.

Attached is a picture of one of my Telrads with the aluminium foil stuck on it with Blutack, which in turn was my attempt to copy the picture that was in US S&T years ago.
Cheers,
Renato