Exposure

Programmed exposure

One of the basics of photography is exposure. Exposure refers to the amount of the light which strikes the film. The correct amount of the light, or correct exposure, is controlled according to the film speed (indicated on the film package, such as ISO 100 or ISO 200), the shutter speed and aperture. Many cameras are now equipped with a programmed exposure function so that the correct exposure can be obtained easily without any guess-work or previous photographic experience.

With programmed auto exposure, the camera automatically sets the most suitable combination of "f "

45stop and shutter speed for subjects at any brightness level. As a result, the correct exposure will be obtained almost immediately. It's an automatic exposure system that means you'll never miss the opportunity to take a photograph. All the photographer has to do when holding the camera is to concentrate on aiming it correctly and press the shutter release button. For example, when you change from a dark to bright subject, the camera adjusts itself to maintain the correct exposure. Anyone can take photographs without worrying about making a mistake.

Now, through the program shift function, it is possible to change combinations of shutter speed and aperture without changing the overall exposure.

Program chart

The chart below is a line chart showing the AZ-4 Zoom exposure program. In response to the use of the macro mode or zooming, the ideal shutter speed and aperture will be set automatically for an appropriate brightness in your photos. As the brightness of your target decreases, the aperture opening is increased and the shutter speed is lengthened. In order to avoid the effects of camera flutter, the shutter speed is automatically set at 1/100 sec. for pictures taken with the flash auto mode. If the format is too dark for an appropriate photo, the flash will fire automatically. In the event that the flash does not pop up, by using the fill-in flash mode, the shutter speed can be increased to compensate for brightness at the EV 4 level, and it is possible to increase the shutter speed up to a 32 sec. exposure by employing the program shift at the same time.

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Olympus AZ-4 Zoom manual Exposure, Programmed exposure