I have just upgraded my scope (Celestron 6" SCT to a WO Zenithstar 81 refractor) and have purchased a guide scope to replace the OAG. I have a dew heater for the main scope but I'm having trouble finding one small enough (10 cm) for the guide scope. I presume I will need one as the cooler months approach but I can't seem to find any of that approximate size... any suggestions?
Also, on another forum, it was suggested that an extended dew shield made from a cardboard roll would replace the need for a heater on the guide scope. Does anyone here use that solution with success?
Hi Frank. I sometimes use a much longer dew heater on my 50mm guidescope.. I just wrap it around more than once
I use PrimaLuce ones at the moment, but also have smaller SVBony ones that fit better (and use USB power).
Thanks Adam, I have considered that (and I also use a Svbony one now) but I thought an extra long heater around the guidescope could overheat it when running at full power.
I have found that an old Kendrick 1.25 inch or 2 inch eyepiece dew strap works okay on 50mm and 60mm finders.
Unless it is extremely heavy dew, you don't need to run these at full power. In SE Qld I have found that the objective lens temp only needs to be a degree or so above the environmental temp to prevent dew forming.
Hi Frank
I use both approaches. I’ve cut the bottom out of a stubby holder and use that as a dew shield, and I also use a small dew heater.
Have a look at camera lens dew heaters on AliExpress - there are lots of them - just make sure you choose a model with the correct voltage (either 12v or usb).
