Flashes of changing color (a result of the celluloid being slightly exposed during the changing of reels), mark the first movements of a plane's steady climb into the blue sky, leaving a condensation trail behind. This 22-second long shot is combined with black and white film, in which diagonal lines and parts of the image are cut out. Though these effects may be highly controlled by the director, at the heart of Condensation Trail is an event which is unique and unstaged, and which is unlikely to ever repeat itself. The plane crosses the screen from the lower left to the upper right corner. Halfway on its journey, a bird flies into the frame and crosses the plane's condensation trail exactly at its very end, making a perfectly sharp diagonal as it slowly reaches for its lower right corner.
