DEVICE FOR WARNING NUMBER OF REMAINING FRAMES OF FILM

摘要

PURPOSE:To attain prior identification of the time for exchanging a film by comparing the signals from a subtractor and a setter for the number of the frames to be warned and warning automatically said number when the number of the remaining frames of the film decreases to the specified number of frames or below. CONSTITUTION:The total number of frames of a film is inputted by the digital signal from a setter 13 for the all number of frames of the film to a subtractor 14. The photographer sets whether a warning is emitted or not when the number of frames attains the remaining number (m) of frames with a setter 15 for the number of the frames to be warned. The digital signal of the number of the photographed frames of the film is inputted by a pulse counter 12 to the subtractor 14. The signal for the remaining number (l) of the frames of the film outputted from the subtractor 14 and the signal for the number (m) of the frames to be warned outputted from the setter 15 are inputted to a comparator 16, from which the signal for the remaining number of the frames of the film is inputted to a decoder 25. When the number (l) decreases to the number (m) or below, a signal line (b) turns to a signal H and the output signal of the decoder 25 turns to the signal H by as much as the number (l) and therefore the outputs from AND gates Al-An turn to (l) pieces of the signals H and (l) pieces of light emitting diodes Ll-Ln of a warning display part 18 are lighted.