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Creating the Time-Lapse Movies
Time-lapse movies were created from the digitized photographs using MATLAB software (www.mathworks.com). The photographs collected at approximately 4-hour intervals (deployments 338 through 383) or 6-hour intervals (deployments 389 through 775) were distributed at an even interval between the start and stop time of the photographic record, as determined from the LED clock. The LED clock time was checked for consistency with camera start times and tripod deployment and recovery times, as recorded in field logs. During some deployments, the camera controller occasionally malfunctioned; in order to provide an equally spaced time series, missed photographs were filled with blanks and multiple photographs were deleted. The LED clock was sometimes set ahead of the true date to maximize the amount of time during a deployment that the clock would display the correct day (for example, the day counter of the LED clock was set three days ahead if the tripod was deployed in February to have the counter be correct during March and April). These offsets are corrected in the time displayed below the data panel. The data plots shown with the photographs were made with MATLAB. The movies were compressed with the Microsoft Video 1 codec using VideoMach (http://www.gromada.com/). This reduced the .avi file size by a factor of about 6.
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