The captured images are stored in memory and output as a movie file as soon as the shooting is finished. 5-second movie takes about 20 to 30 seconds to output.
The resulting movie is shown here.
The occasional blackout is probably a malfunction of the photo reflector. The photo reflector detects reflected light from the infrared LED, but it is located near the lens. When the shutter opens, it probably detects the IR light from the outside world, causing the shooting timing to be off.
There may be room for improvement if an IR filter is attached to the lens.