Is a dew controller necessary?

[Corpze]

I was wondering if there is a need for a dew heater controller if you run with a 12v supply rather than a battery?

Is there any downside of running the dew bands at 100% all the time? Lifespan? To much heat on the scope?

/Daniel

[Owmuchonomy]

I haven't found the need to use one in several years. I have three Kendrick bands running directly off a regulated 12V supply no problem. They do not get hot in a UK climate so I'm sure Sweden will be fine too. They feel slightly warm to the touch. My 9.25" is a massive heat sink anyway.

[ollypenrice]

Agreed. Before having controllers I didn't have them and I haven't noticed any difference. I run them most of the time anyway to slow down the cooling of the Petzvals we have here. (They're sensitive to focus drift while cooling.)

Olly

[baggywrinkle]

You do not need to run the heaters at full power.

Just sufficient to raise the the temperature just slightly above the dew point of the day at your location. Of course a Swedish winter will be a challenge...

[Tinker1947]

I never had a controller on the C11, run 2 band straight off the 13.8v PSU, shorter bands may get a bit hot though.......

[cfpendock]

I've never used a controller.  My homemade bands feel very slightly warm to the touch - almost imperceptible, but they work a treat, particularly on the CPC 1100 which is a real dew magnet.

chris

[YKSE]

I have controller with heater bands, running at median power when needed. I've learned to check humidity at SMHI's weather forecast, when humidity is 80% or lower, I don't turn the heater on, the heat shield is enough for C8.

[MarsG76]

I have controller with heater bands, running at median power when needed. I've learned to check humidity at SMHI's weather forecast, when humidity is 80% or lower, I don't turn the heater on, the heat shield is enough for C8.

Similarly I have a dew controller but I use it all the time with my controller turned up half way.... Haven't seen any demise in quality of views or images. The advantage is that I don't develop any dew ever, needing time waiting for it to heat up once it would.

In theory running the heat straps too hot is supposed to cause internal currents resulting in self made bad seeing... At half way I haven't experienced that.

[Corpze]

Well, where i'm living, we can get down to -35 degrees C, but not every winter, might as well run for the whole year if the summers will be like it has been this year

[YKSE]

If you run the dew heater under the weather like this summer, I'd rather call it life-cycle test for the heaters

[Corpze]

If you run the dew heater under the weather like this summer, I'd rather call it life-cycle test for the heaters

Haha, indeed, le´ts hope for a nice autumn instead :S

[StuartJPP]

Depends on the wattage of the heater...if it is 50W then yes it probably needs one...I made my own to be about 3 watts maximum and they barely get warm, but enough to keep the dew at bay...(which doesn't require much heat I have found).

A dew controller is just another thing to go wrong with even more wires...