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Film - Digital
is the camera aperture?
In photographic terms an aperture is simply a hole that lets light through the light tight housing. This might be as simple as a fixed pinhole in a tin to a variable opening in a complex glass lens controlled through and automatic exposure system.
In both film and digital capture, the aperture is a mechanical means of controlling the flow
or amount of light through the lens to the film or
in the case of digital the CCD,
to make the exposure on the light sensitive material or receptor. This is usually done
through a series of fine over lapping blades that can be controlled
to create smaller or larger openings by rotating a ring on the
outside of the lens. In some situation this can be set manually in a physical manner, digitally in a manual manner through a control on the camera, or automatically by the electronics in the camera.
The essential as aspect to understand is it is an opening that can be varied in size to allow different amounts of light through the lens.
aperture has settings that are measured in f stops - the
larger the f stop number the smaller the opening. While it might
seem strange that this is the case and the f stop numbaers run
in a funny sequence - there is a reason
range of f stops is as follows:
or wide apertures
down or closed apertures
Sometimes it is useful
to think of the aperture like the pupil or iris in our our, where
in light conditions it closes up while in dim conditions it opens
to let more light in
Want to learn more? - do a workshop or one on one with Lloyd Godman