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Important: Your camera must be in manual mode for iterative auto exposure to do its job effectively, as it will assume direct control over all exposure parameters.
There are a few parameters to cover here, so let's get started:
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The desired average grey-luminosity the image should have at daytime resp. nighttime. The algorithm will attempt its best to hit that luminosity within a tolerance of +-5, and it will also try to find a smooth transition between both values during dawn or dusk.
Priority
Contrary to our conventional auto exposure, iterative auto exposure does not work with the cameras abstract EV value, instead it will control the three major exposure parameters itself. These are Aperture (f-number), exposure time (shutterspeed) and iso.
The priority parameter lets you adjust which settings the algorithm should prefer in what order. If your highest priority is exposure time and the image is too dark, it will first increase exposure time to its maximum and only start to adjust the other parameters if it cannot reach the desired luminosity using that parameter.
Dawn and Dusk offset
The transition between daytime and nighttime luminosity is based on the dawn and dusk time of the camera's location, given in the camera configuration above. When these values are set to something else than zero, the sunset and sunrise time is offset to a later (positive value) or earlier (negative value) point of time.
Minimum and Maximum exposure settings
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