GoPros work best in bright light and are optimized for the brightness and color balance of bright sunshine–in short, it’s optimized for fast action in bright light, which is precisely their aspirational target market.
But sometimes you can have too much light, blowing out highlights and washing out colors. And that’s where a polarizing filter can really come in handy. They can reduce glare and saturate colors. They work especially well above water, with snow, or with bright sunshine.
The polarizing filters for the GoPro aren’t circular polarizers like you’d usually use on a DSLR where you rotate one layer against a second layer to control the effect. These are much simpler: single pieces of film, more like sunglasses than a circular polarizer.
Because of that, you can’t expect them to be as effective or flexible as their rotating cousins. Here’s an example of what a polarizer on the GoPro Hero3 does. Neither image has had any post-processing applied to alter colors, brightness, or contrast.
There are a few types of filter for the GoPro Hero 3. One is a filter that snaps on the outside of the housing. They’re convenient, but make sure you get a glass one–the plastic ones scratch easily and that in turn will reduce image quality and risks catching glare. Another is one that sits on the camera itself inside the housing.
I like the filters that are sandwiched inside the housing lens portal (here’s a polarizer, and here’s a red filter for underwater). They’re really simple–just a small rectangle of polarizing film cut to size–they don’t move, they’re protected from scratches, and they stay in place when installed correctly.
For this example, I’m going to use a polarizing filter, but it’s exactly the same process for the red filter. For both, it’s something to prep in advance rather than trying to do it in the field. It’s fiddly, screws can easily go missing, and the filter can easily catch the wind as you’re putting it in. A dry, clean, still work area will make things much easier.
What You Need
- Polarizing Filter + hex screwdriver (supplied with filter) OR Red Filter + hex screwdriver
- GoPro Case
Step by Step
Lay the case flat on its back. It doesn’t make any difference if the camera is in the case or not. Undo the 8 screws around the case’s lens portal.
There are two different sized screws. You can make things easier by laying them out as they come out. If they get mixed up, the short ones goes at the top and the bottom, with the long ones on the sides.
Once you take all the screws out, the black plastic rim comes right off. There glass lens is just sitting there, and under that is the rectangular rubber o-ring. Take the glass filter off but leave the o-ring in place. Take only the top layer off. There’s another layer with just 4 screws. Leave that on.
If you remove the o-ring, it just slots back into the groove. There’s a ridge running around one side–keep that facing up towards you.
Insert the Polarizer Filter
Take your polarizer filter film and place it gently on top of the o-ring. It doesn’t slot in, as such–it’ll be sandwiched in when you do the rest back up. Try not to get fingerprints on the filter (this is where tweezers come in handy).
Put It All Back Together
Lay the glass filter back on top. The edge is bevelled–make sure the larger surface is facing down.
Lay the black edge back around the glass lens and put the screws back in. Do them firmly enough for the o-ring to create a reliable seal, but not so firmly that you thread the screws.