Dew on everything last night

[Wpit]

Well after a full week of rain in Surrey, Thursday night 10th august the sky looked clear and moon free (at least at the beginning). However by 10pm I had dew covering everything, objectives, finderscopes, eyepieces and my iPad. So all my expensive equipment was sadly pretty useless. On a positive note I did relax back and enjoy what I could see with my bins which survived a bit longer from the dewy conditions. So I'm looking for any input on predicting when dew will be worse or is there any online weather resource that anyone has used. 

 

 

 

 

[David Levi]

At the moment I don't have any type of equipment that mitigates against dew. However, I'd just like to comment that it will be a year later this month since I started observing and over that year the worst time for dew, from memory, was August, September and October. I'm thinking that it's due to the warm earth from summer and the rapidly cooling atmosphere at this time of the year when there are clear skies? Anyway, that's just a sample of one year's experience. I look forward to seeing if it's the same in the next year. It's very frustrating though when it happens.

If there's a bit of a breeze then it generally keeps the dew away. I need to get a battery powered hairdryer.

[GavStar]

I noticed the dew was bad last night in SW London. However the dew strip worked very well on my scope and I managed to do 3 hours. Did you use any dew prevention equipment- I also have strips for my eyepieces and finders if it's particularly bad.

Sorry no idea about how to get information regarding predicting bad dew conditions. It would be great if there was one!

[PeterW]

Tried some bino eyeshields.... ended up with foggy eyepieces! Need to make some less enclosed versions. There was a ni in the air and this morning reminded me of autumnal starparties.

PEter

[Davey-T]

42 minutes ago, GavStar said:

I noticed the dew was bad last night in SW London. However the dew strip worked very well on my scope and I managed to do 3 hours. Did you use any dew prevention equipment- I also have strips for my eyepieces and finders if it's particularly bad.

Sorry no idea about how to get information regarding predicting bad dew conditions. It would be great if there was one!

CO has a dew point forecast, don't know how accurate it is.

Dave

[Stu]

It was dewy for me too. Hadn't put any dew protection on last night so my objective got a little dewed up, caused a bit more glare around stuff that usual but I just carried on for a while anyway.

I need to get better sorted with my cabling etc so it is easier to setup.

[Piero]

Quite a lot of dew here too, despite the surrounding trees. No dew on the objective thankfully!  

[Wpit]

1 hour ago, GavStar said:

I noticed the dew was bad last night in SW London. However the dew strip worked very well on my scope and I managed to do 3 hours. Did you use any dew prevention equipment- I also have strips for my eyepieces and finders if it's particularly bad.

Sorry no idea about how to get information regarding predicting bad dew conditions. It would be great if there was one!

Hi thanks for your input, I do have a dew shield on my refractor. But I checkout the dew strips you mentioned. Could you let me know where you got those?

Will

[Wikiastro]

I'd second Clear Outside, which lists the dew point and the temperature near the bottom of the forecast.  If the temperature is below the dew point, dew will form, but even close to that temperature, you'll have a problem on a clear night.  Equipment (and people) lose heat rapidly to a clear sky via radiative cooling, and so your scope will drop below the dew point, even if the atmospheric temperature is above that.  I'm looking at building a dew heater and powering it from a USB power bank - I have a 20,000mAh one here that'll run for hours!

Dave

[swamp thing]

TBH in the UK, you've gotta expect dew every time you observe and be ready to combat it.

I never set up my Dob without the anti dew kit on it nowadays. If I don't need to fire it up that is a bonus but being ready is mandatory IMO.

Have fun out there. 

 

[estwing]

2 hours ago, Wpit said:

Could you let me know where you got those

try F.L.O....at the top of SGL's homepage...

[GavStar]

4 hours ago, Wpit said:

Hi thanks for your input, I do have a dew shield on my refractor. But I checkout the dew strips you mentioned. Could you let me know where you got those?

Will

Here is what I use:

https://www.firstlightoptics.com/dew-prevention/astrozap-dew-heater-tapes.html

https://www.firstlightoptics.com/dew-prevention/hitecastro-single-channel-dual-port-dew-controller.html

[Davesellars]

Yes it was pretty dewy last night here in Oxford as well hitting quite hard past mid-night.  I didn't take out my dew prevention stuff and my finder succumbed however the dew shield on the 120ST is sufficient to keep the dew out for a good while and was not affected.  Everything certainly needed the rest of the night to dry out once I'd got back.  

[AKB]

+1 for heavy dew in Oxford!  I had the shield and built-in heater which all worked fine.  But this morning, I discover a rather nasty smattering of dirty drops on the corrector plate.  Not sure what to do about this... advice anyone?

[Wpit]

Ah well, just glad now it was not just me suffering. It was the finder that got me in the end as I could hardly complete my scope 2 star alignment with a fogged red dot finder. Looks like I need a new budget from my wife for dew strips....

[Wpit]

Thanks for the comments everyone I certain feel better now that I shared the very uk based problem.