Subtronic Nova, Руководство пользователя

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AREAS OF APPLICATION FOR TTL
The flash gun is suitable for the corresponding areas of application according to the
working aperture selected on the flash gun (underwater, the murkiness of the water is also
a deciding factor).
The most effective working aperture for different shooting situations varies according to the
necessary range and the desirable depth-of-field zone. The shallower the f-number, the
depth-of-field zone is reduced. A wide (open) aperture is therefore used when the
background is to remain out of focus. In contrast, a high f-number is used for macro
photographs. A mid-range automatic position is practical for standard shots, e.g. an
exposure from 5.6 to 8. The working range here is approx. 2 meters, which should be
adequate for most underwater shots.
EXPOSURE COMPENSATION WITH THE TTL AUTOMATIC FLASH
To render more saturated colors, it is advisable to underexpose by approx. 1/3 - 2/3
aperture settings , which can be achieved using the + / - correction setting on the camera.
Modern cameras with multiple automatic exposure mechanisms frequently only use the
flash gun as a fill flash in the program setting (
P ). Under water, this produces weaker colors
due to the decreased light output from the flash gun.
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You should therefore use the A setting depending upon the type of camera you are
using. Here, the camera adjusts the synchronization speed to a setting between
1/60 and 1/250 according to the ambient brightness. The aperture can be varied as
required.
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COMPOSITE LIGHT SITUATIONS
In shallow depths, the available daylight is sufficient to expose the film correctly. However,
the primary colors, beginning with red, yellow etc., disappear at increasing depth. The flash
is therefore only necessary at these depths to retain the colors. The most important factor
in composite light situations is a slight underexposure in relation to the ambient brightness.
Example:
Exposure indicator on the camera, measured horizontally in the water: aperture 8.
Aperture setting on the camera in position A or M: 11 or 11/16
Here, the flash gun must illuminate a flashed object by around 1 to 2 aperture settings,
whereas the water in the photograph takes on a deep, saturated blue color.
Composite light photographs can naturally also be taken with the sub-power settings.
Fully automatic TTL flash operation (digital)
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