Dew..... on canon 50mm lens

[Atacamallama]

thought I was going nicely last night doing a widefield milky way shot but instead of a couple of hours of frames I ended up getting 45 minutes because my camera lens (Canon 50mm) dewed up.

any suggestions on how to stop this - rig up my own dew shield (or are they commercial available), are there dew heaters for camera lenses... wiping off the lens between shots (having set a longer pause between shots..)????

Tia for any imput.

[brianb]

Wiping is not to be reccomended ... a low power 12V "hair dryer", for emergencies, should be part of every imager's kit.

You will probably find that the dew heater straps sold for finders or 2" eyepieces will fit your camera lens, wrap it round the barrel below the lens shade unless the lens shade is metal.

[Atacamallama]

thanks for that... what's the right name for the 12v hair dryer, are there any that run on internal batteries or do you have to connect them up to a power tank...?

[brianb]

what's the right name for the 12v hair dryer

They're sold under various brands - e.g. Orion Dew Zapper Gun: Orion Dew Zapper Gun | Telescope Accessories | Rother Valley Optics

As they take a condiserable current (typically 12A @ 12V) running from disposable batteries is not sane. They're happy to run from the sort of power tank you use for running mounts, dew heater straps etc.

[m.tweedy]

use an eyepiece dew band. I dont know if blinky still makes them but I got a couple to put round my camera lenses from him a while back and they are spot on. you could also use a bit of camping mat with a couple of elastic bands as a small temporary dew shield.

[Photosbykev]

I've bought the Kendrick Firefly controller and heating straps for my lens and they work well off a small 12v 7Ah battery. They also make a Firelite system specifically for DSLRs but I found the power connector was too fragile for my taste.