Tuesday, September 25, 2012
No photographs, please!
There is a common misconception that the light from flash units leads to premature fading of pigments. And this is the excuse you most often hear at museums. It simply isn't true. Modern flash units have extremely short flash duration, typically in the range of 1/1000 second. And the energy contained in a flash (or any radiation, for that matter) decreases by the square of the distance traveled. Think about it. How much energy is released by a flash unit? How much actually reaches the surface of concern? How does that compare with normal interior lighting? How does it compare with light coming in through windows? It simply doesn't compute. If there were a constant barrage of simultaneous and continuous flashes 24 hours a day, seven days a week, then perhaps there might be some validity to the argument. But that's very unlikely to happen.
So how did this get started? In the early days of popular flash photography we used flash bulbs. It was not at all uncommon for a bulb to shatter when flashed. The broken glass could be, and was, a hazard. Later bulbs were encased in a clear plastic coating, so shattering was much less common. Still the prohibition persisted, even into the era of electronic flash units, which never shatter.
That's my opinion.