Suitable dew heater for guidescope

[bluesilver]

Hi, I have just managed to get my setup out tonight for a try and didn't go as planned.
My guide scope fogged over in about 1/2 hour.
I have the Orion 60mmguide scope.
https://www.bintel.com.au/product/orion-60mm-multi-use-guide-scope-with-helical-focuser/?v=322b26af01d5

I am looking for a suitable 12v heater that will work with this guide scope.
Prefer to have a 12v cigarette lighter end on it if possible.

As i have never needed or used a heater, I am hoping someone might be able to point me in the right direction to a suitable heater to use on this guide scope.

Any suggestions would be appreciated.
Thanks.

[sunslayr]

This (https://www.ebay.com.au/itm/193040448453) 25cm heater on eBay should fit, I use it on my 60mm.

[Fox]

Hi Peter, I imagine you'll need potentially two or even 3 heaters. One for the guidescope, one for your main scope, and I believe some cameras can even dew up. You'll need a dew controller unit (often have a cigarette lighter power plug) and there are a range of dew strips depending on circumference. Bintel has the Kendrick range, and heaters for ZWO camera's (note: I've got no idea about camera heaters though). Fox

[bluesilver]

Thanks for the replies, link and advise.
Will take a look at the ones on ebay.
I will also look into one for the main scope, i have yet to have any dramas with the main scope fogging, but i am sure it will only be a matter of time.
Appreciated.

[gregmc]

If you want to save some battery and only heat to the level needed, don't use the dew controller with just the variable knobs to control the power (varies the PWM width like a light dimmer so average power is controlled)

Use a controller which at least can keep your guidescope front perhaps 3 deg above the ambient air temperature (it has a sensor for ambient and a sensor that is placed next to heater around guide scope). Kendrick digifire from Canada or local at Bintel is an example. The extra cost with this I think is worth it not to heat up scope more than necessary and also save battery power.

A better option is a controller that can keep the sensor above the dew point. In addition to the ambient temperature sensor, it also has a humidity sensor. This will save even more battery power.