Abstract: In a method of measuring the flash duration of a flash unit, the momentary light intensity is converted into an electrical signal that is determined and stored, and that is delayed by at least that time interval that exists between the beginning of the flash curve and the maximum thereof. The stored maximum is compared with the delayed signal, with the flash duration being determined from the signal obtained thereby. As a result, at the maximum of the intensity/flash duration curve, the information concerning the rising leg of this curve is still available. The apparatus comprises a sensing element for the flash intensity, with the sensing element being followed by a time-lag element and a peak detector, the outputs of which are connected to a comparator, the output of which is connected to a time-interval measuring circuit.

Abstract: A device for measuring color temperature, having at least one measuring diffuser and at least one indicator for the color temperature, as well as operating elements for turning the device on and off, for resetting the measured values, and for initiating a measurement. To be able to easily and rapidly set or adjust the color temperature, the device has at least one adjustment control element for at least one remote control transmitter for adjusting the color temperature of a light source. A photographer can set or adjust the color temperature in a remotely controlled manner via the adjustment element and the remote control transmitter.