2014-01-24

Fogging-Free Heroes

«Dry Suit» for my HD Heroes.
Lately, my GoPro HD Heroes have been massively plagued by fogging when filming under water. And this after years of fog-free operation – despite (or because) of the anti-fogging strips that GoPro sells.

While I could salvage most of my footage by declaring it to be a work of true art, I yet had to find a working solution. It seems that I was successful in keeping my Heros free of fogging...

When it comes to defogging means, Silica gel immediately comes to mind. Of course, there are gazillions of dealers for this common desiccant. I opted for a domestic dealer that also handles orders in smallest quantities fast and accurate: Aquapac-Aquaman Deutschland GmbH. Their desiccant actually isn't silica gel, but mineral material and Montmorillonit clay.

Fogging-free Heroes: GoPro
cam and housing are stored separately,
each with a bag of «silica gel».
On purpose, I didn't order any unpacked silica gel: otherwise I would have to get suitable packs that also have the required permeability. And when using some cloth pack, the color indicator isn't visible anymore. Why the hassle when I get the bagged desiccant for small money?

A first test of the product delivered was more than satisfying: I packed the desiccant into the GoPro housing and stored the HD Hero cam into its own small container, together another bag of desiccant. After some time I put the HD Hero 3 back into its housing and let it operate for 45mins out in the cold at 4°C. Even at the end of this test run there wasn't any fog inside the housing, and especially the front lens was completely clear. I didn't used any of GoPro's anti-fogging strips (whose effectiveness is frequent subject to discussion anyway).

I'm storing the unused desiccant bags in their separate protection bags to avoid loading them. The MD-2g desiccant is for use with the (empty) GoPro Housing, while I'm using the MT-3g for storing my GoPro HD Hero cams dry (in some small and air-tight storage boxes). You can get an impression from the photos in this blog post.
  • I'm using the desiccant type MD-2g in the GoPro housings as there is no danger of corroding it in case a bag should break.
  • In contrast, I'm using a different desiccant type MT-3g for keeping my GoPro HD Heros dry: in case a bag should break, its contents won't corrode a Hero's metal front panel.
As this first test run worked out as desired, I'm eagerly waiting for the in-field results.
Update: In the meantime, my real-world test in 4°C cold water went extremely well. So I can really recommend this method.