Submitted by admin on Fri, 2005-10-07 11:00. ::
The first flash bulb was designed by Chauffour in 1893 for use by underwater photographer . It contained magnesium inside a glass bulb filled with oxygen under pressure. A platinum wire heated by passing an electric current through it ignited the magnesium. Boutan was not as sometimes suggested the first underwater photographer, the honour probably belonging to Englishman William Thompson in February 1856. Boutan was not even the first to use artificial light underwater, since the Frenchman Ernest Bazin had experimented with an electric lighting system at an underwater observatory in 1872. Little is known of Bazin's work and none of his pictures appears to have survived, Boutan was an early underwater photography -although his mechanic Joseph David apparently took better pictures, and he was the first to make use of flash underwater. Even without the flash, Boutan's camera housing weighed 400lbs, though this weight will have been less noticeable underwater.
Perhaps surprisingly it was not until over 35 years later that flash bulbs became commercially available. Dr Paul Vierkotter improved on Chauffour's design in an Austrian patent of 1925. Further work patented by German Johannes Ostermeier in 1930 led to the first commercially available flash bulbs - apparently on the market slightly earlier. These were called 'Vacublitz' and used tin foil as the metal. They were soon joined in the UK by the 'Sashalite' and in the USA by the 'GE20' flash bulbs. The 'Sashalite' was named after the famous portrait photographer who had played a part in their design, and was made by the General Electric Company for 'Sashalite, Ltd.' These early flash bulbs were the same size and used the same bayonet fitting as normal UK light bulbs; the advertisements warned the user not to fit them into domestic sockets but only the special battery powered flash reflector unit. These units cost £1-10s, then a reasonable weekly wage for a worker (£1.50 or roughly $2 in today's currencies - but perhaps more than a hundred times this to allow for changes in the value of money) and the bulbs were 101/2d or 1/6d (4p or 7.5p). The larger size was said to be suitable for 'taking groups, dinners etc'.
Aluminium was often the metal used in early flash bulbs rather than magnesium, though later this was mainly replaced by zirconium wire. Although safer than flash powder, bulbs were not without their dangers, many exploding and showering the subjects with glass. Photographers were warned always to use the flash bulbs in a reflector, not just to direct the light toward the subject, but also to protect them from flying glass. You could buy covers for some reflectors to shield close subjects from the glass as well, though few photographers bothered.
In later years, bulbs came with a lacquer coating on the glass which meant that most of the pieces of glass where held in place when the bulb exploded. They also had a small indicator spot at the bottom, which was normally blue. If their was a crack in the glass or other leak that allowed air to enter the spot (perhaps cobalt chloride) would turn pink, probably due to absorbing moisture.
Various different types of flashbulbs were made, differing in the light output and other features. Most later bulbs were much smaller than the originals, but high output bulbs remained quite large. Bulbs also differed greatly in their burn times - from less than one hundredth of a second to several seconds. Flash bulbs generally had a colour temperature of around 3800K, special bulbs were produced for use with daylight balanced film with a blue coating to increase the colour temperature to around 5,500 - 6000K, at the cost of some loss of light. There were also special infrared flashbulbs as well as those with a high UV content and other specialised types.
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