Lynx astro dew heaters

[ninjageezer]

Just acquired a pair of Lynx Astro dew heaters and mini dew heater controller. Used but great condition.

I used them last weekend and was quite surprised after being on for 3 hours + outside in 5c temps that I could not really feel any warmth. I did try them laid flat off the scopes and do get a small bit of warmth on the inside but to me I think it would not be enough to be of any use, any one got any experience with this make please ,I run them of a large leisure type power pack 12v. I have nothing else to compare to.

[cajen2]

I suppose the simple answer is, if it's dewy, is your scope dewed up or not? If not, they're working!

[Grant93]

I have some cheap dew heaters off Amazon. When I go to pack away after a night of imaging, I can feel the dew heaters are ever so slightly warm, all you need to prevent dew is to keep the glass above the nights dew point, even if its only a degree, so to my belief, these things don't need to be significantly warm, just enough to keep it hovering above the dew point. Still yet for it to fail me.

I assume this would be very different if you're using something with wide aperture, so need the heat to travel further. Could be wrong though, just a guess.

[edarter]

Needs to be just enough to keep the temperature just above the dew point but no more, you don't want to create warm air thermals!