I like to follow this principle. “The more skills you have, the better your chances for success.” I used to use this principle as a climbing instructor when teaching students rope systems. Inevitably on some climb something wouldn’t go right, maybe a simple thing like getting a rope stuck. The more rescue and climbing systems you knew, the better your chances of having a solution to fix the problem.
The same is true for photographers. Every photographer has a story about a ‘photo shoot gone bad.’ Strobes don’t fire, talent doesn’t show up, permits aren’t in order. What separates one photographer from another is how they deal with these situations. Clients like photographers who have solutions, not problems. Knowing more technical skills behind the camera also helps. And one of my favorite things to do is add gels to flash to spice things up.
Gels are heat resistant pieces of material similar to plastic. They come in a variety of colors and sizes. Many speedlights today come with gels in the box. Some diffusion dome caps are colored to simulate the effects of gels. Why use gels? Because they allow you to change the color of light. Some gels are more theatrical in use. Blues, reds , yellows are great for dramatic splashes of color in an image. Other gels are for color correction such as orange (CTO) and blue (CTB). One of my favorite techniques is using an orange gel, a full CTO, and changing my white balance to incandscent. Setting your white balance to incandscent changes normal daylight to blue. If you underexpose your shot by 1 stop or more, that color turns to deep blue, almost purple. Your speedlight has about the same color balance as daylight. The flash would also be blue in this scenario. Adding an orange gel counter filtrates the flash and brings the color temperature back to daylight. Anything the flash hits should look about normal. Take the fishing image here. I wanted to add some mood and drama to the image, and using this gel technique did the trick. I shot at a slow shutter speed to get a nice blur to the water, and underexposed the daylight to get a purple color.
There are many places to purchase gels, but the biggest supplier is Rosco (www.rosco.com). They have precut gels in their Strobist Collection that work perfect with speedlights.