How Does Aperture Affect Flash Exposure? – Beginners Tutorial
Aperture is a key setting in flash photography, controlling how much light enters the camera and how it affects both ambient and flash-exposed areas. In this beginner-friendly tutorial, we’ll break down how aperture changes flash exposure, when to use a wide or narrow aperture, and how it impacts background brightness. Whether you’re shooting portraits or products, understanding aperture will help you get better flash results. Stay tuned for a simple and clear explanation!
This video is from our Off-Camera Flash Photography Course.
Video Summary:
This video explains the relationship between aperture and flash photography. It quickly recaps aperture basics (a wider aperture/smaller f-number creates shallow depth of field; a narrower aperture/larger f-number creates deep depth of field). The key lesson is that aperture affects both flash exposure and ambient (natural) light exposure equally, as it controls the size of the hole all light passes through. Opening the aperture (smaller f-number) makes the entire image (flash and ambient areas) brighter. Closing the aperture (larger f-number) makes the entire image darker.
Timestamps:
0:06 – Introduces the topic: how aperture works with flash.
0:14 – Reviews the inverse relationship between the f-stop number and the size of the aperture hole (small f-number = big hole; big f-number = small hole).
0:35 – Recaps aperture’s creative role in controlling depth of field (shallow vs. deep).
1:32 – Explains the core principle: Aperture equally affects both flash exposure and ambient light exposure because both light sources travel through the same lens opening.
2:58 – Practical demonstration using a series of images.
* 3:12 – Shot at f/4: Aperture wide open, both ambient and flash light are bright.
* 3:31 – Shot at f/5.6: Both exposures darken slightly as the aperture closes.
* 3:39 – Shot at f/8: Both exposures get darker.
* 3:44 – Shot at f/11: Image becomes significantly darker.
* 3:50 – Shot at f/16: Aperture is very closed, resulting in a dark image with insufficient light from both sources.
