Astro log: Nov. 13th, 2009

Equipment: Orion Skyview 6 Deluxe EQ and Celestron Astromaster 76 EQ, using the 32, 25, 15, and 9 mm eyepieces and the ultrablock filter.

New objects observed: dew

Previously observed objects: M31, M32, M42


I had had great hopes for this night - the sky was going to be clear for a long time for the first time in ages, with halfway decent transparency to boot. I went and set up my shelter and scope early in the night, but found that there wasn't a whole lot out that I could look at early on, so I went back inside, leaving my stuff out for later.

When I came back out, I was a bit surprised to find that massive amounts of dew had settled on everything. Still, it wasn't the end of the world. I started looking around, but found that I was having a really hard time finding anything in my finder scope. Then I noticed that I was having a tough time seeing anything at all. Finally I shined my red flashlight on my eyepiece, and saw that it was fogged up. Oh no!

I tried swapping other eyepieces in, but that didn't help. The primary mirror was fine, at least, but I still couldn't see anything. Eventually I noticed that the secondary mirror was fogged up, so I packed everything up and took it back into the garage. I pointed the 6" upside down to dry out and left the lens case open so that could fully dry out as well. I took the 3" out for a spin for a while and was able to see M31 (but not M32) and M42, but not with the same detail as with the 6" of course. I am not, however, sure how much of the difference was from the size of the mirrors and how much was from any dewing on the 3".

After a while, I brought the 6" back out and was able to observe M31, M32, and M42 briefly, but it dewed up again within a few minutes and I gave up. I have begun researching anti-dewing solutions and will try them out next time the weather permits observation.

Comments imported from the old site.
$25 dew sollution

Hair dryer. Works well enough and is cheap.

Glad to hear you got out.


I was also going to look at making a foam dew shield, and possibly using a small old baby blanket as a shroud. I bet I could place an order, such as it is, with my mother in law; she goes garage sale-ing a lot and brings home all sorts of junk. I bet she could find me a hair dryer.

I had also read about using a big-ass umbrella

But I thought about it some more, and I think that would be unworkable in the shelter, sadly.

dew shield

Yeah, just be careful and have it plugged in to a protected circuit, dew collects on them too. It scares me some times to turn it on.

Have you found that your shelter has helped cut down on wind? I had a rough night out a couple of weeks ago with a pretty stiff cold breeze.

Last week was great, you should check out my 2 newest images.

I do have a protected circuit out there

And we turned up a hairdryer that I thought was my wife's, but turned out just to be some hair dryer that had been following me around for god knows how long (probably an ex's from long ago) that has a trip thing on it too. Score!

The shelter helps with wind to a point. If it gets too windy, then I have to take it down, otherwise it's like standing in a box of sails. The other night I just went out with hat, WWII Army coat (like in my Twitter pic) and gloves, and it worked pretty well.

comments powered by Disqus