When photographers start using gels, it’s important to understand the creative and technical potential they unlock. Gels are flexible tools that allow you to add color for dramatic effects or correct color temperatures in different lighting conditions. This article will help you learn how to use gels effectively for both purposes, starting with the creative side.
Dramatic Color Effects
One of the most exciting uses of gels is to add bold, eye-catching colors to your images. Gels work by placing a colored, translucent sheet over your light source, which changes the color of the light it emits. The key to making gels stand out is understanding how they interact with shadows and highlights.
How Gels Show Up in Shadows
Gels tend to show up best in shadow areas of a scene because shadows lack direct light, making the color from the gel more visible. When light from a gel hits a shadow, there’s no competing light source, so the color can be strong and vibrant. To achieve this:
1. Use a dark background: A darker environment or setting naturally has more shadows, allowing the gel’s color to show more dramatically. This works well when you want an intense, artistic effect.
2. Position the light off-axis: If you place the gelled light to the side or behind your subject, the shadows cast on the side of the subject that the main light doesn’t hit will be filled with the gel’s color. This contrast between the regular light and the colored shadow creates a dynamic, three-dimensional effect.
3. Use complementary colors: Combine a neutral or warm key light with a contrasting gel color, such as blue or purple, in the shadows. This interplay makes the color pop and adds depth to the image.
4. Control the exposure: You can deepen the intensity of the gel color by slightly underexposing the ambient light or using lower power settings on the key light. This makes the gel’s color more dominant in the shadows.
Layering Multiple Colors
For more complex creative effects, you can layer different colored gels. One technique is to use a cool color like blue in the shadows and a warm light for your subject. The contrast between warm and cool tones creates a cinematic feel, which can make portraits, fashion, and even product shots stand out.
Transitioning to Color Correction
While gels are often used for artistic expression, they can also be a practical tool for balancing light sources in a scene. When you have different types of light in the same environment—such as daylight, tungsten, or fluorescent—gels can help you create a cohesive look by correcting color temperature differences.
Matching Color Temperatures
Different lights have different color temperatures. Daylight is cooler, while indoor lighting (like tungsten) tends to be warmer. If you’re shooting in mixed lighting conditions, the scene can appear disjointed unless you correct the color temperature using gels. Here’s how:
1. CTO Gels (Color Temperature Orange): These gels warm up the light. Use them when your flash or strobe is cooler than your ambient light. For example, if you’re shooting with tungsten bulbs indoors (which are warm) and your flash is daylight-balanced (which is cooler), a CTO gel will bring the flash closer to the warmth of the indoor lighting.
2. CTB Gels (Color Temperature Blue): These gels cool down the light. Use CTB gels when you’re in a daylight setting but want to cool down the flash to match a warmer indoor light source.
3. CTG Gels (Color Temperature Green): These are used to correct fluorescent lighting, which often has a green tint. If you’re working under fluorescents, placing a CTG gel on your flash can neutralize the green cast, helping the flash blend better with the ambient light.
Practical Steps to Correct Lighting
1. Identify your light sources: Before applying gels, analyze the types of light in your scene. Are you dealing with daylight, tungsten, or fluorescent? Once you know the light temperatures, you can choose the appropriate gel to balance the flash or strobe with the ambient light.
2. Gel the main light: If you’re using flash as your main light, add the gel needed to match it to the dominant light source in the scene. For example, if the ambient light is tungsten, apply a CTO gel to your flash to make it warmer and blend better with the scene.
3. Maintain consistency: To ensure a consistent look across the entire image, it’s important to balance all your light sources. If you have a mixture of window light and indoor tungsten light, you may need to apply different gels to multiple lights or adjust your camera’s white balance to unify the color temperatures.
Combining Color Effects with Color Correction
There are instances where you can mix both artistic effects and color correction. For instance, you can use CTO gels on your key light to match tungsten ambient light and then add a dramatic gel, such as a deep blue, to a secondary light for creative background accents. This allows you to balance the overall scene while still injecting some visual flair.
Final Tips for Using Gels
Test the exposure: Gels reduce the amount of light hitting your subject, especially for color correction gels, which can affect the overall exposure. Be prepared to adjust your flash power or ISO to compensate for the light loss.
Start simple: If you’re new to gels, start with one color effect or one color correction gel at a time. This helps you understand how gels interact with your scene without complicating things.
Use grids or barn doors: To focus gelled light in specific areas like the shadows or background, use light modifiers such as grids or barn doors to prevent the color from spilling onto areas where it’s not needed.
By understanding how gels interact with light and color, you can transform your images from simple to striking, whether you’re looking to add dramatic color or balance mixed lighting. Mastering these techniques will open up a world of creative possibilities and improve your technical control over different lighting situations.