This time-lapse camera could be used to record images of cathode ray oscilloscope screens. The glow from the phosphor on the screen of an oscilloscope persists for a short time, so even if the beam passes only once across the screen to record a transient event, it can be seen and photographed.
This camera was probably built in the Physics Department Mechanical Workshop. One use of this camera was recording the trace of a CRO connected to an ionospheric recorder. Every minute a pulse of radio waves was sent up to the ionosphere and reflections were detected. The strength of the reflection depended on the electron density, and the time delay gave the vertical height of the layer.
The 35mm film was developed and the data measured from the negatives. In later years, Polaroid 'instant' cameras were able to record one-off events more conveniently.
This item is part of the UQ Physics Museum Oscilloscopes Tour
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NH, JDB, SN