Dew Shield

[recceranger]

Guys,

I will be getting a Pulsar Obs put in at the end of the month and it will house a CPC 1100.  A quick query - has anyone got experience that could tell me if I would still need to use a dew shield?

Rick

[RT65CB-SWL]

I will be cautious and say "Yes!"

[Tinker1947]

I would think so, get one with a heater built in, you can always turn the heater off due to the size you won't need to have a voltage adjuster, my C11 had a Heated Dewshield and a heated strip out in the open there's a lot of glass to keep clear.....

http://www.firstlightoptics.com/dew-prevention/astrozap-flexi-heat-dew-shields.html

[michael8554]

Yes

And in this weather condensation will build up on the inside of the dome and on your kit even when you're not using it.

Michael    (Pulsar 2.1M and 8" LX200GPS)

[Ken82]

I would be cautious of buying a dew shield with a heater . If you have a Guidescope on top and counterweights on the bottom the dew shield only comes with one notch as I found out . Best to buy a standard dew shield and dew heater !!! Actually sometimes I just use the heater if it's windy 

[acey]

Any piece of glass that is directly exposed for long enough to the British night sky is going to dew. If the scope is inside a dome but can still see the sky, it will still dew. It's happening because the sky is colder than the glass, so the latter radiates infrared to it, and this heat loss chills the layer of still air on the glass surface. Solutions: shield the glass as much as possible from the sky, or get air moving across the glass (can be cold air - wind is a natural dew preventer), or use heat to evaporate the dew. Or give it a wipe with your sleeve

 If I were going to put my scope inside an observatory I would continue to use whatever anti-dewing measures I use normally, which in my case is a camping-mat dewshield. And when I'm not looking at the sky I don't leave my uncapped scope pointing at it. If I had an observatory then I suppose that between viewings I might adjust the scope or roof so that the optics were shielded from the sky, especially if the scope were to be left unused for a relatively long period of clear sky (e.g. while writing notes, nodding off, answering a call of nature, etc).

[brantuk]

11" Sct and dew shield/heater? Essential, either with or without a dome, is the answer I would give.