ebercovici

I was on a tour of the Biosphere 2 in the mountains north of Tucson with my Sony A7R3 and my Sony/Zeiss Vario-Tessar 4/16-35 lens. The first stop on the tour, after the introductory video, was a tropical rainforest environment. My viewfinder image was totally fogged, presumably due to fog on the sensor, although it is possible that the fog was on the front element. The camera had been outside, where the temperature was in the low 40's. By the time we had gone through the ocean environment into the desert space, the fog had dissipated. A man in our group with a Canon DSLR experienced the same problem, but those with sealed cameras, such as cell phones, did not have a problem. I have two questions: Would I have had the same problem if I had been using a lens with a better seal, such as a Zeiss Batis? Would I have been able to avert the problem if I had run the camera for 20 or 30 minutes on video prior to the humid environment in order to heat up the sensor? Would this have been a safe technique?

CHG_CANON Loc: the Windy City

If you could keep your camera warm, near body temperature, like your cell phone in your pants' pockets, you probably wouldn't have had a problem. If your kept your camera in the car, on the floor say next to a hot-air blowing heater and went straight from the car indoors and kept the camera inside a jacket near your body during the video, again probably, you would not have had a problem. Both approaches are cheaper and more effective than a new expensive lens that might only keep fog off the sensor. My experience recently going from cold car trunk in Milwaukee to steamy indoor flowers had fog on the sensor, fog on the lens front and fog on the viewfinder and what seemed like 30-minutes to clear.

Stardust Loc: Central Illinois

It was purely science - taking a cold, glass object into a warmer, very humid environment will cause condensation. Happens often to people who wear glasses (unless specially coated).

As Chg_Canon covered, warming the camera prior either works or at least cuts the time considerably for the camera to reach "room temperature".

DWU2 Loc: Phoenix Arizona area

Based on my past experiences with fogging, I'd say the issue was the lens, not the sensor.

Bill_de Loc: US

I wonder why the OP didn't look at the lens at the time???

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