Some early cameras had fixed or extremely limited aperture settings.
The aperture of a camera is the size of the opening in the lens through which light passes to imprint the photograph onto the film or digital recorder. Knowing the aperture at which a photograph was shot can help you re-create similar effects in later photographs, and can help you to better understand the technical qualities of photography. A photo taken with a small aperture, for example, will have a larger depth of field than one taken with a large aperture. Calculating the aperture on your camera is a simple equation.
Instructions
1. Determine the focal length of the lens by reading the file's metadata, consulting your camera's on-screen information, or simply looking at the lens itself if it has an indicator on it.
2. Find the f-stop value for the photograph by consulting the file's metadata, or simply looking at the setting on your camera. Film cameras will have a knob for the f-stop, and digital ones will display this information on the LCD screen.
3. Divide the focal length of your lens by the f-stop at which the photograph was taken to get the aperture of your lens for any given photograph.