Cloudy eyepieces

[TransparentBadger]

Good morning

Just a quick question. I noticed last night that as I was observing my eyepieces kept fogging up. It seemed like last night everything was a dew magnet (thank goodness for my dew shield). Even my binoculars became unusable due to the lenses misting up. Has anyone got any tips of how to avoid or combat this problem? I'm sure I read somewhere not to wipe any of the lenses in the field due to the possibility of scratching the optics.

Thanks in advance

James

[gkec]

Dew heaters are obviously one solution but tend to be expensive and yet another thing to get the hang of. I use a quick blast from a hairdryer however that is not much use if you don't have mains.

I did try a 12V car fan heater but that drained the power pack in seconds which resulted in me tearing all over the house trying to find the extra long extension lead and a hair dryer.

I have been on the lookout for a gas or battery powered hair dryer and have found show dog owners and caravaners want them as well. The show dog owners in particular are very interested in where to buy these but they seem to only appear at booths at dog shows. (Not for me but each to their own!)

However I have just found this

http://www.capitalhairandbeauty.co.uk/hairdressing/electrical/hairdryers/oobi-hairdryer.html

which at £20 may be worth a try.

[damnut]

Hi There,

A 12v hairdryer is a great addition, my friends use proper boxed 12v leisure batteries to power dew control, hair dryers, mounts etc, if you use anything less than a decent size and capacity battery it will discharge rapidly.

Try keeping your eps in a pocket until use then swap as needed. You can also get small dew strips for your ep's.

Cheers

[TransparentBadger]

Thanks both for the prompt replies, I'll follow up the leads. It really was quite a problem last night. My housemate used the binoculars and was telling me he could see what sounded like nebulosity near Jupiter. Once he'd left I took a look and sure enough, the lenses had misted over giving a lovely misty halo to all the stars

[earth titan]

I've battled dew (being the owner of a C9.25 dew collector) to the extent I now use dew heater tapes on everything. I have a 12v hair drier for mobile observing, which works really well.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[John]

The trick is to keep your eyepieces a little warmer than the outside temperature. Unlike the scope, which needs to have cooled, eyepieces can be used a bit warmer. When they get too cold even the warmth from your eyeball can fog them.

I keep mine in their foam lined case with the lid shut when they are not in the scope. The foam seems to keep them just a little warmer than ambient. Popping them in your pocket for a few minutes works too.

[TransparentBadger]

They were left out on the table, so that would probably explain the problem. I'll get a little box for them and try again and see what happens.