Create a series of still photographs in a computer file format, such as JPEG. Alternatively, generate the photographs from an existing video, with video frame extraction software, or from a camera that automatically takes photographs sequentially at predefined time intervals.
Start Adobe Flash Professional. Click "Timeline" in the "Window" menu. Position your cursor over "Frame 1" in the timeline. Select "Frame 1," then "Import to Stage" from the "Import" menu, located within the "File" menu. Navigate to the first photograph file in the time-lapse movie, using the controls in the "Import" dialog box. Click the file name, then click the "Open" button to place the photograph on the Flash stage. Repeat this step for all the files used in the time-lapse movie.
Position your cursor over the "fps," or "frames per second" text box in the timeline panel. Type "50" to specify a frame rate. Each frame will be displayed every 1/50th of a second, or every 0.02 seconds, when the movie is played.
Click "Test Movie" in the "Control" menu to play the time-lapse movie. Determine from the play back whether the time-lapse movie should be played slower or faster. Increase the number in the "fps" text box, if you want to speed up the time-lapse movie. Decrease the number, if you want to slow down the time-lapse movie.