In tricky lighting conditions, knowing how to balance different light sources is crucial. When you get it right, your photos look natural and well-composed, without any harsh shadows or blown-out highlights.
Coming to you from Mark Wallace, this informative video breaks down the concept of the “exposure diamond.” Wallace takes a common scenario—shooting in a dimly lit apartment with bright sunlight pouring in through the windows—and demonstrates how to balance the uncontrolled ambient light with the light from a flash. The exposure triangle, which includes ISO, aperture, and shutter speed, is expanded into the exposure diamond by adding flash power as a crucial fourth element. Wallace explains that while ISO and aperture affect both ambient light and flash exposure, the shutter speed only controls ambient light, and flash power only impacts the light from the flash. This separation allows you to fine-tune your lighting for a balanced result.
In the video, Wallace begins by setting his camera to manual mode, choosing a shutter speed of 1/60th of a second and an aperture of f/7.1. These settings give him flexibility to adjust the ambient light. He then dials in his ISO based on the ambient light meter reading, which lands at ISO 800. This ensures the ambient light is properly exposed before he introduces the flash. By metering and adjusting the flash power, Wallace brings the subject into balance with the background, demonstrating how minor tweaks can lead to a well-exposed photo.
Wallace also addresses a common issue: reflections from the flash in windows. He offers a simple solution—moving the light source or adjusting the flash angle—to prevent unwanted reflections. The key takeaway here is that balancing light is not just about technical settings, but also about creatively solving problems on the spot. Wallace emphasizes that once you understand how to control both ambient light and flash independently, you can start to manipulate the light to create the exact look you want, whether by making the background darker or altering the flash intensity to suit the scene.
The video concludes with an on-location shoot where Wallace puts these principles into practice. He balances the sunlight streaming onto his subject with the flash, achieving a natural look. Check out the video above for the full rundown from Wallace.
If you would like to continue learning about how to light a portrait, be sure to check out "Illuminating The Face: Lighting for Headshots and Portraits With Peter Hurley!"
