Smart 'new' dew removal idea.

[Moonshane]

Hi all

As if the rapid arrival of a load of cloud to a clear sky before I sat down to have something to eat with the family wasn't bad enough, I was rapidly becoming aware of Jupiter looking a little blurry.

Is it my contacts? No. Is it my fogged eyepiece? No. It's my fogged up secondary! A first for me in my dobs (both solid tubes) and therefore I haven't bothered with a dew cap on them until now. So I made one rapidly from some foam sheets I have but alas too late of course. A fogged secondary can be a right pain I read, and I don't have a 12v hairdryer and really don't like blasts of even warmish air on cold optics.

So a bit of lateral thinking and I realised I have a cold air 'hairdryer' in the form of a 12v inflatable mattress pump which we use when camping. It also has an outlet valve a little smaller than the 1.25" hole in the focuser. Put it in and left it for a few minutes and worked a treat.

Hopefully the dew shield will now 'dew' its job but if you have one of the blowers for camping it's worth using it to get you out of 'trouble'. Would also work well on EPs too I suspect but I tend to keep them in my case and swap intermittently to ensure they remain above ambient. I am working on getting a dew heater and a tape or two and this will solve the EP problem.

Cheers

Shane

[nobbytate]

Thats a great idea Shane iv,e got one of these and never thought of using it.

Thanks for for that i must try it out

John

[Moonshane]

If you could wrap a few winds of tape around it, I bet you could use it in the focuser on 'suck' and it would work as a cooling fan if you leave the caps on?

[Doc]

The simple ideas are always the best. I have two of these left after the blow up beds went bust.

[Rusty Strings]

Nice idea, unfortunately mine would wake the dead if I fired it up in the back garden.

[yesyes]

Same problem here. I have a mattress pump but that would wake up anyone in a 5 mile radius. Hard to believe but it's even louder than my CG5-GT mount. ;-)

But I do like the idea. Could build a quiet one with a nosepiece, a funnel and a bigger computer fan. ;-)