Archived posting to the Leica Users Group, 2009/11/16
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Slobodan writes: "Didn't Forscher modify a Nikon with lights, in order irradiate the elmusion for low light shooting?" ------- I don't know if Forscher was the first to do this but pre-exposure and latensification used to be old tricks of available light photographers and cinematographers to eke out the last residue of sensitivity of films. Pre-exposure involved exposing the film to low light levels either prior or after exposure. The idea was to get the image exposure over the toe of the sensitivity curve. It effectively provided an increase in apparent sensitivity of 1/2 to a full stop. Latensification involved exposing the film to mercury or ammonia vapors prior to exposure. It could also gain a one stop increase in sensitivity. These techniques are rarely used today in this era of ultra high speed films. You can find more about them by looking through old photo books and magazines. The use of lights in cameras was described in 1950s era magazines such as "35 MM Photography". One construction article suggested gluing 4 grain of wheat incandescent bulbs on the inside of a Leica M camera near the corners of the frame. The lights would be illuminated briefly by a battery switched on by the flash contacts. The article suggested that this would work well with B&W film but might give problems with color film because the lights would upset the color balance of daylight emulsions. I never tried gluing bulbs to the inside of my camera but I did experiment with pre-exposure and latensification. Both worked but there was too much variability in the process and it proved to be far more trouble than it was worth. Larry Z