The first shipboard installation of the Kelvin & Hughes rapid processing photographic radar system has now completed 500 hours service aboard the P. & O. liner Canberra and the navigational and technical staff in the ship have had a reasonable opportunity to evaluate the equipment from all practical aspects. The advantages of this type of display are, in summary:

(1) A full size plotting screen (in this case 24-in. diameter) is available for direct plotting.

(2) All operations may be carried out in broad daylight without the necessity of having to accustom the eyes to a dimmed PPI.

(3) There is no radar hypnosis. Information is presented as a solid, steady picture at the end of each cycle.

(4) A permanent record of the radar information is immediately available for playback at any later date.

(5) Several officers may view the screen at the one time and discuss the plot while it continues uninterrupted. This is a very favourable point in a large vessel of high speed where three or more senior officers may wish to know at all times exactly what is happening on the radar plot.

(6) By using a processing/exposure cycle of seven seconds or more, a build-up of picture strength, true track of vessels, &c. is possible.