Different ways I use flash gels


People that have known me for a while know how much I enjoy using shoe mount flashes to get different looks for my photography. While I often share my wilder shots I’m happy to report that I can take shots without flashes, light modifiers and colored gels. In fact, when I’m shooting for clients I start with simple shots and when I’m certain that I have shots that they’re happy with I’ll see if there’s some interest in pushing things into more creative places. Most of the time my photo subjects have grown comfortable enough with me near the end of a shoot that they’re willing to try some different lighting setups to see where the shoot goes.

To get different looks I’m big on using flash modifiers like grids, barn doors, softboxes and colored gels. I use velcro straps from Honl Photo and LumiQuest and I use gels from Flash Zebra, GAM and Honl Photo. I take a ton of gels with me on a shoot and to keep things organized I’m using Case Logic CD cases (I picked mine up for about $5 each at my local Best Buy). For this blog entry I want to talk about colored gels and some of the different ways that I like to use them on a shoot.

Using gels to match the lights in your environment

The first way I like to use flash gels is to get the color of my flash to more closely match the rest of the light in a scene. This is probably the most common use for color correction gels. To give you an idea what this means, if I’m shooting in a room that is lit with fluorescent lights I’ll throw a cut of CTG gel on my flash. I do this because the camera sees fluorescent light as having a green tint. To over come this green tint you can choose a fluorescent white balance setting on your camera (or in Lightroom/ACR if you’re shooting RAW) and everything will look totally normal. If you didn’t add the green gel to your flash anything that you light with your flash will look completely different in color. Not using a color correction gel can make it look like you used a flash. That’s not too good when you’re trying blend your light with the ambient light.

The most common color matching gel I use is Color Temperature Orange (or CTO) because it matches my flash to the common incandescent lightbulb that is in almost every home. When you shoot in a room lit with normal lightbulbs you set your cameras white balance to tungsten. By putting a CTO gel on my flash I match the color temperature of my flash to the rest of the light sources in my room. Here’s a look at a full strength CTO gel on one of my LumoPro LP160 flashes:

Using flash gels to add color

The second way I like to use gels with my flash is to create color from my flash. I love using pure red and blue to throw some color onto my background. For me it’s an incredibly powerful way to tell a story with an image. It’s also a great way to add a unique look to a rim or hair light.

I also use CTO gels is to warm up a subject. If I have a subject that has a pale complexion I add between 1/4 and 1/2 strength CTO (orange) gel to the front of my flash to instantly give my subject a much warmer look to their skin tone. The general rule is that people look more pleasing if they are warmer. If you’re wondering how effective this technique is just look at the color of the bulbs used in some funeral homes above the recently departed (it’s very orange while all the other bulbs in the room are normal).

You can also use a gel to mimic a lighting scene that doesn’t exist. For example, if it’s cloudy and very overcast but you want to simulate the color of a warm evening sunset then you can add some orange gel to your flash to give everything you illuminate with your flash a very warm feel.

Another way of getting warmth into your final shot is to try a different color temperature. Cloudy white balance will add a little warmth to the image. Shady white balance will add even more warmth. Add a cloudy or a shady white balance to flash with an orange gel and you’re really making the world take on the feel of late evening sunlight.

Using flash gel to change the color of the world

This is a technique that has it’s roots in the film days when special filters on your lens worked with color balanced film and gels on a flash to shift part of your picture to look one color while maintaining a very neutral color balance for your subject (illuminated by your flash with a colored gel). Using gels like this can be tricky and it helps to have some knowledge of what happens when you play with white balance and the color of your flash.

I’ll explain this technique by using a picture I took on a recent engagement shoot. I wanted the sky to be darker blue then it was but I didn’t want my subject to be blue (which happens when you shift the entire image towards blue). To get my final shot I color balanced my flash with CTO gel and I set the camera to use a tungsten white balance. You can do this in Photoshop but doing it in camera has the advantage of letting you see what the shot will look like on your cameras LCD the second you capture the shot (or on your computer screen if you’re shooting tethered). It also saves you a lot of time in Photoshop.

Lets start by taking a look at the RAW file captured with daylight white balance and a full cut of CTO gel on my flash:

I know that my Subject, Wendy, looks very orange. That’s actually what I want because we haven’t adjusted white balance yet. What I want you to look at is the background. The sky is absolutely accurate and so is the background. That’s because my orange flash didn’t affect the sky or the background. It looks accurate but it’s not what I want it to look like. That’s why I used the orange gel on Wendy.

Now, let’s take a look at what happens when we change the white balance to tungsten:

Wow. What a difference that made. The obvious difference is that Wendy no longer has that orange look to her and her sweater is really red. Unlike the first shot she now looks completely accurate. But what I’d like you to take a closer look at is the background. See how it’s now much bluer?

That’s because the tungsten white balance setting shifts color towards blue. It does this to balance light sources that are orange. By lighting my subject with orange flash and setting the camera to tungsten I ended up with a subject that looks correct and I pushed the background to blue. And it all happens without Photoshop (or Lightroom). Awesome!

But if I want to really finish off this shot I still take it into photoshop to calm down some of the places where I may not want blue in the background. I have my own techniques for removing blue casts from an image but one of the simplest ways to do it is to create a Hue/Saturation/Lightness adjustment layer. If you change the color from master to blue (this is a drop down menu at the top of the adjustment layer panel) and you drop the saturation slider you are removing the color blue but leaving most other colors alone. Invert the layer mask and you can use the brush tool to apply your adjustment only where you want it.

Here’s a look at the same image but with some of the blue color removed from the trees that are in the background:

And this is the final image I delivered to Wendy. I was able to show her almost exactly what the shot would look like before we left the location. Why go through all this trouble? I do it because I wanted Wendy to pop off of the background and a warm subject in a warm environment just doesn’t have that kind of separation. By shifting the colors of the background away from the color balance of my subject the image looks closer to how we would see this scene with our eyes. This contrast between subject and background is something you try to achieve when you’re looking for something different than what can be captured with a camera phone or a point-and-shoot camera.

This is just one example of how to use white balance and colored gels to change the look of the background of your image. With the fluorescent white balance setting, for example, you’ll be adding magenta (purplish red) color to your image but whatever you light with a green gel on your flash looks correct. Using this technique can get you some interesting results at sunset if you’re not getting enough excitement from your sky.

I hope this helps you to think of some new and exciting ways to use gels on your flash and how to combine those gels with white balance settings to create totally unique images (in camera) that will help you tell stories with your photography.

To really get the hang of this technique it’s best to just play around until you hit on a combination that you like. I highly recommend experimenting with gels and white balance settings and seeing what the results are. With digital cameras it won’t cost you anything to experiment and If some of your shots turn out crazy that’s OK. Just delete them and I promise not to tell anyone what happened.



1 thought on “Different ways I use flash gels

  1. Pingback: Location Portraiture | Adding People to your Landscape Photography | SonyAlphaLab.com | Sony DSLR Reveiws, Alpha, Nex, SLT, Cyber-Shot, Sony Lens Reviews

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