Posted 23 September 2022 - 03:30 PM
- Astronoob76 likes this
Posted 23 September 2022 - 04:08 PM
I've suffered the same problem, using a bino bandit. Rich V suggested to me an air bulb blaster, and I've used that idea with some success. If you have 120v power handy any hairdryer (set on the lowest setting) makes quick work of it. I've also looked into ~$25 12v "hair dryers" from Amazon. The reviews are horrendous, and I imagine they would be if that was your intended use, but I think they might work okay for clearing the fog (not frost) off of optics.
Posted 23 September 2022 - 04:19 PM
That's one of the features of the Celestron 15X70 Skymaster Pro binoculars which was worth paying the extra for the "Pro" vesrion. These are nitrogen purged and with the eyecups not being too long, I find that they do not fog up.
Clear skies and keep looking up!
Posted 23 September 2022 - 04:37 PM
Posted 23 September 2022 - 05:05 PM
It reads like your problem is with the ocular fogging up, not the objective. I do two things when this is a problem.
If it isn't cold enough to require gloves I'll hold the eyepieces in my hands to warm them a bit when I rest my arms.
Another thing I do is put the binoculars inside my jacket for a few minutes to warm them. I'm fortunate enough to have several binocular sets so on very severe fogging nights I switch instruments with the unused instrument inside my jacket. It seems that the air between our eyes and the ocular lens can become so humid it raises the dew point above the temperature of the ocular lens. The inside the jacket trick also works when the objective lens fogs up. It works better if you put the binoculars in there before or at the very first sign of fogging. When I go out with only one instrument, I just use the warming time to do naked eye observing looking for meteors or upgrade my constellation knowledge or whatever.
I know that equipment buffs add value to the hobby by telling us about tricks with gizmos and gimcracks but what I like about binocular observing is its equipment light approach. I've considered putting a hand warmer in a beer cooler to keep the binoculars above the dew point but haven't tried it yet. I think of this when I feel the cold air enter my loosened jacket as I do my trick but never think of it as I'm heading out.
- Mark Y. likes this
Posted 23 September 2022 - 08:11 PM
Dear CRN3371, I was not referring to dew forming on the outside surface of the binoculars. I believe the original thread was about the optics "foging up", not the formation of dew.
Clear skies and keep looking up!
Posted 23 September 2022 - 11:33 PM
Edited by crn3371, 23 September 2022 - 11:34 PM.
Posted 24 September 2022 - 02:55 AM
Another thing to be careful about is that your breath rises up into your eyecups, so blowing out or otherwise deflecting your breath sideways can reduce the problem. I made a face visor for my binoculars that fitting above my nose so my breath is fully blocked.
- Jon Isaacs and j.gardavsky like this
Posted 24 September 2022 - 09:20 PM
Does the film from the wipes affect the optics at all?
Also would the lenses need a wet cleaning to get off residue later?
Never thought about using them until this thread.
Posted 25 September 2022 - 04:39 AM
- j.gardavsky likes this