Starved flies were released into an enclosed flight chamber (diameter 0.3 m). Three orthogonally aligned high speed cameras (Kodak MotionCorder, 5000 frames per second, shutter speed 50 µs, resolution 146 x 88 pixels) were aimed on a small region in front of an odor-baited visual target (3 cm high and 1 cm wide cylindrical vessel containing a drop of vinegar). Arrays of near infra-red (λ = 880 nm) LEDs covered with diffusive paper provided the back lighting required for image capture in a spectral range well below the flies' sensitivity (S1) and hence did not compromise the visually-mediated components of the animals' flight behavior. Hungry flies will orient toward dark vertical objects in the presence of attractive odors (S2). As they approach, they either land on or saccade away from the target as it looms within their visual field (S3, S4). Six complete object-avoidance saccades were captured and analyzed.

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