Leaving a 40d out over nigtht

[apetty]

I was thinking of setting up my camera on a tripod over night and having a

remote fire off pictures every 30 minutes or so. I was wondering what to do

about the Dew? Do you cover the camera body in a plastic bag or is the 40d built

to withstand that kind of moisture? Is it even an issue? What about the lens

(Most likely Sigma 10-20)

[zml]

Wrap (loosely) a plastic bag around it and secure it with some gaffer tape. I park my camera outside quite often (in pretty hot and humid weather of D.C - the bag is very dewy in the morning) w/o any measurable adverse effect, but consider the possibility of rain...

[apetty]

I've got the same weather(I'm near Hagerstown about 1.5 hours west of DC), the rain is something I didn't think of (Can I get a resounding DUH from the group LOL)

 

I guess the bag should cover as much of the lens as possible.

[peter_popp1]

Make sure you use a lens hood, and then you can cover the entire setup with a single piece of

plastic that attaches on the lens hood. The lens hood should then stop any condensation on

the front element.

[john_frie]

If you know it's not going to rain you might want to leave the plastic bag off unless you get

up early.When it starts to warm up after a cool night you may risk getting a condensation

build up inside the bag that could deposit unwanted moisture and/or droplets onto your

camera. It doesn't take much just a small amount of liquid to find it's way inside.

[geoffm]

If you <drape> the bag over the camera, leaving it open at the bottom, then you don't have to worry about either dew or condensation. A couple of bits of tape should secure it against breezes.

[zml]

Geoff: Yep, the word "drape" better describes what I do, but in my (and OP's as it turned out) neck of the wood humidity in summer is so oppresive that the bag is totally wet and the camera more-less "dewy" in the morning. OTOH without the bag (and I'm positve that there are other ways, but a plastic bag costs nothing...)the camera is soaked - I have lost a nice Canon F1 due to constant dew/condensation.

 

 

As far as rain is concerned instead of plastic bags I use a Kata raincover: it is fiddly like hell and needs to be taped to the lens hood, but protects the camera well, unless you point the lens up that is...

[danielransom]

You can buy camera ponchos. Not sure about condensation, but they sure look like they keep the water out. I wouldn't do it unless the camera and lens are fully weather sealed.

[theo_dibbits]

Why not wrap it in cling film?

Theo

[wilbur_wong]

Astronomers have used really long lens hoods, on the order of a length extending twice the diameter of the objective lens. Of course they use this with very narrow field of view lenses (telescopes). This way, all the dew forms on the extended hood while the front element stays dry from dew.

 

For more than a passive approach, there are also mildly heated approaches which actually would work better for short exposures than it does for hours long exposures. For telescope work, the heated air causes diffraction of the air and causes the focus to shift constantly.

 

Depending on how severe the dew issue is, you might get enough heat to last most of the night by setting a 5 gallon bucket of hot water under the tripod. . . . .