I had a very strange e-mail from a viewer in which he commented on my 'Mullard in the early 1950s' blog article, in particular my commentry about the Mullard LSD flash tubes. He went on to lament that my article was just like most others on the 'net, a few words on these devices just copied from other websites!!!@*'?
I must admit, I was flabbergasted, what nonsense, why would this person act like a radio part - hint - the bit that you turn to get more volume.
Anyhow, in order to satisfy any other affectionados of the Mullard LSD flash tube here's a litle bit more about them - not copied from anywhere on the web but instead from my own personal experiences as well as Mullard official archive sources.
All of the LSD series of flash tubes were fitted with a B4 base, below is a photo of my own personal twin head LSD 3 flash system which I use with a period Hasselblad 1000F camera. Each Xenon filled tube tube can muster a maximal energy discharge of 100J - quite a belt as this equates to half the energy a defibrilator outputs to kick start an ailing heart! Each tube operates at a 2.7 KV anode voltage and utilises a minimum trigger voltage is 4 KV. Flash duration is 100 microseconds with a light output of 3000 lumen-seconds.
As a vintage flash system these are quite special, I can remember being captivated by photographs taken by Alec Perlman of a couple ballroom dancing which were published in a 1950s edition of The Rollei Way and knew I would have to have a set. Sure there's no thyristor control and you have to think in order to use my vintage flash but the rewards are a motion stopping well lit scene without a hint of harsh glare which go to produce some of the most beautiful silver images out there!
Some of you may be aware that the LSD series of flash tubes were developed in conjunction with Ilford Photographic who are still going today as the last bastion of Black & White silver image film and paper - look em up at harmantechnology.com
Below, I have an official Mullard photo showing the inventor (middle checking his wallet) being interviewed in June 1950 for the television programme Picture Page which was filmed as an outside bradcast at the Engineering Centre in Glasgow - is it still there, 62 years later in Sauchiehall Street I wonder?