Controlling dew inside my observatory ....

[SlimPaling]

Hi ...

I am trying to find ways to cut down on condensation in my Roll Off observatory .... my kits seems to get pretty damp in the winter months despite there being plenty of ventilation.

I am currently using a couple of greenhouse bar heaters controlled by a standard timer switch during the nights which seems to help a bit.

A friend has suggested that I might try to incorporate a humidity controller ( like : https://www.amazon.co.uk/dp/B083BRFK3R/?coliid=IAPJC7W3RZGA1&colid=2QHVF4PDG6ZPZ&psc=1&ref_=lv_ov_lig_dp_it )  which could then switch on or off the tube heaters.

Before I go ahead and spend any money .... does anybody have any experience of using one of these contollers for this purpose?

What “Relative Humidity” setting do I set the controller to to give me some chance of success???

Mike

[AstroKeith]

Your title says 'dew', but it sounds like you meant condensation when the roof is shut?

I find continual low steady heat best.

Problem with a sensor and switch, is the scenario when the observatory has got cold, and then the sensor kicks in and starts the heater, but the air will heat quicker than the equipment, and so you'll get condensation form on the equipment.

I have a 60W greenhouse heater under the scope, with a loose cover thrown over the top. 

[Carbon Brush]

I my shed observatory I have a dehumidifier and small heater.

The dehumidifer has a hose (rather than it filling a container) and a drain hole in the wall.
When running the device, the fan circulates air, ensuring all of the shed air is moving. No damp corners.
The waste heat from the process lifts the temperature a few degrees, further encouraging exaporation.
This looks after the scope, mount and unboxed kit in general, including a desk computer.

Of course this does next to nothing for drawers and the like containing eyepieces, cameras, etc.
I have a total of 30W (I think) tube heaters under drawers holding eyepieces, cameras, etc.
This lifts the internal temperature a little and encourages convention around the drawer body.

These are switched on as required. I have not tried to automate them.

Seems to work for me.

David.