do multi-reticle RDFs dew up?

[WayBig]

I'm thinking of a multi reticle RDF for my dob - the type with a glass screen, onto which circles are projected - similar to this http://www.f1telescopes.co.uk/shop.php?id=1660&level=

My question is - do they dew up? is a dew shield available, or easy to bodge up for one?

Thanks

[m.tweedy]

I'm thinking of a multi reticle RDF for my dob - the type with a glass screen, onto which circles are projected - similar to this http://www.f1telescopes.co.uk/shop.php?id=1660&level=

My question is - do they dew up? is a dew shield available, or easy to bodge up for one?

Thanks

Yes they do Dew up.

Solution-one of these

Kendrick Red Dot Finder Dew Heater :: Kendrick Dew Control System :: Altair Astro

[pvaz]

Yeah they do.

I got a telrad and used a black plastic cut to be curved around it, then used some adhesive Velcro sick half in the telrad and the other half on the plastic. It makes for a very nice dew shield and its very effective. Total cost was about 3€.

I based the design in a similar one on a thread in the DIY section.