•Do not use flash bulb (or unit) with following types of film because it does not couple properly.
Flash bulb of guide number 14 with ASA 25 film, guide number 20 with ASA 800, and guide number 28 with ASA 400 or higher speeds.
• In flash photography using a conventional electronic flash unit or flash bulb when the proper f/stop is set according to the guide number, there is a heavy drain on the mercury battery. Therefore, be sure to return the aper- ture ring to the "A" position after shooting.
•When the subject is too far or too close, the shutter button cannot be depressed.
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