----- Original Message ----- From: "Jerry Lehrer" <jerryleh@xxxxxxxxxxx> To: <rollei_list@xxxxxxxxxxxxx> Sent: Tuesday, May 31, 2005 10:40 AM Subject: [rollei_list] Re: Flashbulbs > Richard and Peter, > > I just dug out my GE book "Photolamp & Lighting Data" > printed in 1963, which shows all the GE flashbulbs of that > era. There WERE M2s, M3s, and M5s (which bore no > relation to #5. The M bulbs all had a miniature pinless > base. > > They showed the #50 bulb which produced 5 million lumens > in a Edison screw base. > > Jerry > The GE No.50 and Sylvania No.3 were meant to be used in studio reflectors with very slow shutter speeds (1/25th or longer) or open flash. A single bulb in a 12" reflector has a guide number of 600 for ISO-100 film. Thats f/6 at 100 feet folks, try that with your stobe units. Remember, these are bulbs about the size of 150 Watt household lamp. --- Richard Knoppow Los Angeles, CA, USA dickburk@xxxxxxxxxxxxx --- Rollei List - Post to rollei_list@xxxxxxxxxxxxx - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org - Online, searchable archives are available at //www.freelists.org/archives/rollei_list