which dew controller/heater?

[garymck]

Hi,
looking for advice on which dew controller/heater to buy..... Last week was trying to image in melbourne and had huge problems with dew on my guidescope.... never had a problem before, so took a while to figure out why I kept losing guidestar ....duuuhhhhhhh, kept looking for clouds!!!! Not really competent to build my own....Cheap would be good...if there is anything that is cheap in this hobby....

cheers
Gary

[MikeyB]

Cheapest solution = 12V hairdryer (around $30 at camping gear shops)

[TrevorW]

My understanding is you don't really need a regulator just a 12v power supply if you use the plans available on the web for the dewheater strip

[wasyoungonce]

Quite right.

Generally speaking people use controllers to reduce the energy consumption and give longer life (hrs of operation) when using batteries. Especially in the field.

I use one (controller) and only try to input the smallest amount of energy needed to keep dew at bay...however..generally speaking there should not be a issue running heater straps straight from 12V..or at full energy. Especially if you are not concerned with power consumption.

[NorthernLight]

Hi Trevor,

can you pls post a link to the site where making of stripps is explained?
Here in Auckland dew is even worse than in Melbourne and I keep reading things about dew control even for eyepieces. I experience problems with fogged up eyepieces when I just put my eye to it.
I can run the lot from a transformer but would like to be able running it from a 12V DC 24A/h power tank, too, without having to go home after just 2hours in the field.
I know the solutions offered at shops but would love to be able to do it myself-for the pride and cost savings.
thanks in advance!

[Octane]

Max,

I use a DewBuster system with a series of Kendrick Firefly dew heater straps. Works a treat.

On my FSQ-106N, I have one on the dew shield, and one on the focuser drawtube to try and maintain temperature equilibrium. I also have one on the finderscope. The DewBuster system accepts two temperature sensors (you really ony need one, though, as I can't imagine there being such a huge temperature difference within the space of 1 metre square).

Check out the Dewbuster web site. It mightn't be the cheapest solution at $200, but, it has alleviated the need to keep taking a hairdryer to the optics, as well as running a dew strap 100% all the time. I set the temperature i wish for the strap to reach above ambient (typically between 5-10 degrees) and forget about it for the rest of the night. It takes care of everything.

H

[erick]

"Cheap would be good...." :rofl:

Thousand Oaks controller.
Dewnot heater straps.


(Actually cheaper than many many other hobbies and sports).

[beren]

Last time out with scope and the gear I encountered some extreme dew and cold {:P for Perth anywhy} which prompted some research to upgrade from my trusty old Kendricks basic controller to something a little more advanced. Gone for the Dewbuster system to, yet to receive it but so far Ron keating has been a pleasure to deal with and transaction hassle free.

[hikerbob]

I use the Dew-not heater straps and so far am very pleased.

http://www.dew-not.com/Order_Form.htm

I started trying to make both discrete resistor types and nichrome wire ones and was unhappy with the direction both were going. A small range of straps and all the smaller optics are fine. The only issue so far has been keeping a 10" corrector plate dry all the way across, about 1/2 dry in bad conditions. Hopefully some shielding will help with that.

Bob