With the mechanical shutter cameras the exposure [the amount of light getting to the film emulsion] is determined by two things.
1. The length of time [1/60th of a second for example] the shutter remains open to admit light from the subject, to the film emulsion surface. This is true for both focal plane shutters, and shutters built into a lens.
2. The diameter of the opening in the iris diaphragm [the device you set, utilizing the "f-stop" setting on a movable ring on the lens] in the lens.
The larger the diameter of the opening, the greater the area of the opening, and therefore, the more light allowed to enter at any given time. My memory is not what it used to be, but I think I recall that for every unit of increase of the radius of the iris diaphragm opening, the amount of light allowed to pass is increased by a factor of 4 times!
Also, if I recall correctly, each of the "clicks" [detent positions] on the f-stop ring represents a change of the amount of light passing through the lens by a factor of two times [refered to as one "stop"].
With the new digital cameras, the "shutter speed" is NOT mechanical, but controlled electronically. I do know that some of the digital cameras with interchangable lenses also still have the iris diaphrams, allowing one to control depth of "field," or focus. I am not certain about the presense of a mechanical diaphragm in the less expensive digitals which do not have interchangable lenses.
I hope this helps you to begin understanding the basics of exposure, until an expert can improve this answer.j3h.
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The Photographic Vision - 1984 Controlling Exposure 1-6 was released on: USA: 1984
Wear a badge containing photographic film.
P. K. Turner has written: 'Photographic exposure'
The change irreversible. You cannot re-use photo film.
A film badge can be defined as a device containing photographic film that registers the wearerÕs exposure to radiation. The badge consist of two parts, photographic film or dental X-ray,and a holder.
A film badge can be defined as a device containing photographic film that registers the wearerÕs exposure to radiation. The badge consist of two parts, photographic film or dental X-ray,and a holder.
When undeveloped photographic media is exposed to light or radiation (x-rays included), it can be exposed. It can also be damaged by exposure to water or other liquids. Physical damage can also be done by rough transportation, like rips, tears and folds.
There is no specific collective noun form photographic film, in which case a noun suitable for the context is used, for example a roll of photographic film, a case of photographic film, an archive of photographic film, etc.
Exposure compensation is a tool built into cameras that allows the photographer to adjust the amount of light entering the camera. It allows an amateur photographer the ability to take great shots.
Set the camera to Auto mode so that the camera will adjust it self according to the situation.
different kinds of photographic rays