dew shield

[johnkirkpatrick]

I have an old camping mat about 1 or 1 1/2cm thick and was wondering if it would be any good for a dew shield fr m scope? (sig).

And how long wouldI cut it too and would it effect my views, An how the hell do I fit it so it is easily removed and fitted without marking my scope?? ( sorry if letters missing am using a cordless keyboard and t aint great lol)

[Merlin66]

Yes it would do the job nicely, but I've never needed a dew shield on a newtonian!

The general rule is length = x1.5 the aperture. A wrap of Velcro tape usually holds it pretty firm onto the tube , just allow 60 -70mm dew shield overlap onto the tube.

[Skills]

I just fitted a dew shield on my 200p made from a camping mat, secured using a Velcro strap from b&q (92cm x 5cm). I cut four holes for the big screws on the side of the scope so that the mat went up against the focuser. Made one for the finder and rigel too as that was really suffering.

Adrian

[lukebl]

I thought I'd never need a dew shield on my Newtonian, till the secondary started misting up with these damp nights. I use a rolled up bit of cardboard. Not very pretty, but it works.

[bcfcciderhead]

Here's mine with camping mats on, was not sure if the primary needed doing but had some left over so thought "what the hell".

Was not sure i needed to do it as well Lukebl as i been hearing that Newtonian's dont suffer, but after a night out last week the whole OTA tube was was wet with dew so that made me do it.

Just a quick note, the mat goes on an extra 80mm past the end of the scope to stop dew going down to the eyepiece.