# Sigma 20 ART + Condensation



## oscaroo (Jul 19, 2016)

Gday.

As a happy owner of a Sigma Art 20mm f1.4; I have found myself - twice now - suffering from trying to take photos and realising the front element is fogged up.

This is something that I haven't experienced generally until now.

The first time this happened I was up on a mountain at night, with two layers of wind-proof clothing and a "feels-like" of -12C. My sigma lens was initially okay. But then, a few minutes into taking photos it started fogging up behind the front element. So I switched to my 8-15mm L fisheye, and that one didn't have any problem. (Both lenses were in the car cabin before I went out - the fisheye being in a pouch while I used the sigma before it fogged up).

The second time this happened, it wasn't that cold. It was 9C and I had been driving in the car (a hatchback) and stopped to take some photos. Inside the car it wasn't that hot either. It was maybe 17C. I went out to take photos and saw that my viewfinder was hazy. I looked at the front element of the sigma, and water had condensed on top!. I wiped with with my tshirt, which didn't help; I wiped with my hoodie that was in the car, and i wiped and wiped until there was no water left, then once more with the microfibre cloth, and back to photo taking.

This weekend, I'm going to the snow and was hoping to carry my camera in my backpack (with batteries on my person) and well, do I take the Sigma? Previous experience shows that it'll probably fog up or condense. Is my Sigma dodgy? or does it have something to do with the Sigma NOT having "weather sealing" and the fisheye having it? NB: My other lenses, 24-105L and 70-300L have never fogged up either.

Thank you for your time.


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