Dew Heaters

I find that they work fine on medium size SCTs pretty well,
I have a 12" and find that I must use a dew shield with the kendrick heater, and even at that, I eventually get dewed up.
SO I bought an adjustable power fan heater which I use to clear the plate when dew comes, it ruins viewing for a small while but it does the trick.

Just one thing I found about a dewed corrector plate with an SCT, I find it much easier to collimate the scope like this as the twinkling effect of the atmosphere is blocked out and all you can see are the diffraction pattern in the out of focus star as the image is very still. You need to use vega or some other bright star for this. Give it a try next time you scope fogs up.

Dewbuster looks great though I went for the BC and F which is equivalent to the Kendrick system. I see BC and F are doing the temperature controlled type too now.


M