To be sure that they flash when you shoot, clean the fitting. Remove dust and corrosion before using them.

A dry Scotch Brite will do the job and you'll be sure the bulb fires !

Take care about the flash itself. Despite the fact that the sharp pointed loaded center contact normally will assure positive lamp contact, it is quite normal after so many years that the contact has become dirty or corrosed.

They may look the same, but they're real different.

Flashbulbs may be grouped in 4 classes according to the time of peak of illumination and some other characteristics.

 Class F(ast) Bulbs: peak of illumination within 5 milliseconds.  GE SM and Wabash SF 

Class M(edium) Bulbs: peak in 20 milliseconds.   Photoflash # 22 and Super-flash Press 40 and Westinghouse #11


Class S Bulbs: peak in 30 milliseconds. Photoflash # 50.

Bulbs for 4x5 Focal Plane Shutter!


Sylvania 2A FP (Focal Plane) E27 screw.
Comparable to GE No.31 or Philips PF45

Class FP: long peak focal plane shutter bulbs such as the # 31 and Sylvania super-flash No. 2A

Sylvania 2 A -formerly Wabash- for use with up to 4 x 5" Focal Plane shutter.

Long peak bulb for use with the focal plane shutter for stopping the action at 1/1000 sec.

160 Ft or 60 meter 80.000 lumen.





Speed Midget flashbulbs have a single contact bayonet base for quick insertion. Overall length 2 1/2 inches. 

Speed Flash flashbulbs. The effective flash duration last about 1/100 second with the SF and 1/200 for the SM at 1/2 peak

These bulbs are recognizable as they do not have wire or foil inside the bulb. The flash of about 5000 lumen seconds is produced by the primer mixture on the tips of the two lead in wires, igniting in an atmosphere of oxygen.



The GE # 5 Synchro press

Efficient Bulb for use in midget reflectors. Very popular with the press. Not suitable for the Focal plane shutter for speeds more than 1/30 sec.


The G.E. # 6 Focal Plane 

A midget bulb with longer flash duration designed for use with the miniature focal plane. Camera size 35 mm to 2 1/4 x 3 1/4.

As you can see these bulbs are unsuitable for the larger 4x5 inch camera. Duration is too short


The upper side of the picture is dark, due to the fact that the GE#6 peaks too short to cover the 4x5 inch sheet film, during the time the focal plane shutter slit, travels along the film surface. We'll need Special Bulbs

Focal Plane No. 31 and Superflash no. 2A

These bulbs are designed for use with the larger focal-plane shutters up to 4 x 5 inches in film size. They have an extend peak of illumination, which is required for the focal-plane synchronization. Not to be used with front-shutter synchronization. The effective light output of these flashbulbs is around 80.000 lumen seconds.

Instantaneous Flash with 4 x 5 

Focal Plane Shutter 4x5      
Film speed ASA/DIN 100/21 125/22 400/27
Shutter speed 1/200 - 1/250 130 180 260
Shutter Speed 1/400 - 1/500 90 130 180
Shutter Speed          1/1000 65 90 130


Synchronization with Other Models

Because of the many variables involved, Graflex does not supply any accessory device for synchronizing Graflex focal-plane shutters. Various attachments for this purpose are on the market, and their manufacturers should be consulted for all information regarding them.


Bulbs are still available from Bill Cress.

the worlds largest remaining distributor of Flashbulbs




the right 


A Graflite synchronizer is to be connected with a solenoid cord # 26703 2 x male. One male connector is a household connector with flat prongs and the other one is a connector with small round prongs. fig. 3

A Heiland synchronizer is to be connected with a solenoid cord: 1 household to 1 Bi-post female.

The Household to Bi-post sync cord connects the solenoid outlet on the battery case with the magnetic solenoid tripper on the lens board.

The solenoid if tripped by the red shutter main switch on the battery case, pulls the tripper from the shutter.

The female Bi-post Synchronizer connector doesn't fit to the shutter.

You can order your customized cord with the tips or plugs you want at Paramount.



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