How to Use Old School Flashes for Outdoor Photography – PictureCorrect: "On a dull day, it can be used to simulate sunlight and add contrast to a photograph. In this situation, the flash is the main light source, and its direction should be above and perhaps to one side of the subject, just like sunlight. This entails the use of an off-camera flash. It’s important to remember that even on a dull day, the natural light is directional, and when used correctly, the flash should augment that natural light."
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