PDA

View Full Version here: : Dew heater


v8torrie
22-05-2024, 07:48 PM
Hi all. I'm somewhat a newb at this hobby. Working on removing as many things as possible that get in the way of a good data collection.

So now I am at a point where I need better dew control. I have a william optics 61mm scope and think it's time for a dew blanket.

What's some solutions that people have used on a similar scope without needing house mains to run the rig.

AstroViking
23-05-2024, 09:50 AM
I have an 'SVBony' brand dew-heater from eBay that's USB powered. It plugs into the powered USB hub (2.4A) and keeps my scope dew-free. If I'm using the DSLR, then I have a large capacity battery pack that will power it all night long.

There are many options available and seem to be split between 12v and 5v (USB-powered), along with a multitude of controllers to drive them - some smart with auto-temperature/humidity sensors and some merely a potentiometer to control the voltage reaching the heater.

Cheers,
V.

cafuego
25-05-2024, 09:04 AM
I got an MSM brand dew strip off Amazon (https://www.amazon.com/Dew-Heater-for-Telescope-Camera-Lens/dp/B092887BQ6?ref_=ast_sto_dp) that keeps my 72mm diagonal zoom lens nice and toasty. It runs off USB and has three power settings.

With the lens hood on the zoom lens I seem to only ever need to run it at the lowest power (in western Victoria, which is not necessarily known for being particularly humid ;-)

I can power it with a phone charging brick for a few hours if I use it with the DSLR or I can plug it into my asiair mini and run it off the battery pack that way.

OzEclipse
26-05-2024, 10:35 AM
Depends a little on how heavy your dew is.

Up to about 3 inch diameter glass, telephoto or refractor, i have found the cheap USB / 2W heaters work perfectly well in moderately heavy dew. In really heavy dew, just give up and go to bed. I bought a pack of 3 in 2015 and they are still all working.

One got snagged once and the pull caused all the heating elements to bunch up. Amazing it didn't rip the electrical leads out. It still keeps the dew off. I just put the heaters at the bottom so the heat rises across the lens surface. I mainly use it for a finder scope now and use the others for the imaging optics.

Joe

v8torrie
27-05-2024, 09:53 AM
I appreciate the feedback. I have invested in a usb powered heater yesterday. Will test it very soon hopefully

GaryPHayes
11-02-2025, 12:11 PM
I have tended to leave my dew heater on full blast when the ambient and dew temp get close - but probably not the best way to do it. Like you keen to find out what the best brand would be - just to use with a nice big powerbank and leave running on ify nights