Gear/Technique: Cross Polarization for Reducing Reflections and Specular Highlights

I accidentally pulled of a Soul Reaver at the church when I switched from ambient light to flash, lol

Anyway, this is the first time I've used this cross polarization technique outside of portrait photography.

Since the client wanted pictures of these figures behind glass panels, I used external flash (2 speedlights on light stands) to drown out the reflections of the surrounding area lit by the ambient light. However, the external flash itself then also appeared in the reflections in the glass as well as the varnish of the surrounding wood panels.

My workaround for this new issue was to use cross polarization by putting a polarizer in front of my lens and polarizing film in front of my 2 external flash units.

Below is a comparison of the ambient light shot versus the shot with cross-polarized lighting.

For reference, below is a comparison of plain flash (i.e. no polarizers) versus cross-polarized lighting.

Besides the significantly toned-down reflections of the speedlights in the glass, note the lack of glare on the wood panels. On the flip side, some of the colors turned out a bit funky despite a gray card being used to maintain white balance.

I had tried this same technique before in portraiture in order to cut down the specular reflections on oily skin without having to rely on bulky light modifiers such as soft boxes. However, I stopped using the technique after that convention when I realized that the technique doesn't work well with the hair or the eyes.