Light Sources for Contact Printing. By Sandy King(Underlined items in text represent links.) This article is presented in two parts. Part One is a general introduction to the types of light sources that are used for printing with the alternative processes. In this section we discuss the general operating parameters of some of the various light sources commonly used in alternative printing. Part Two compares the two types of light systems that are practical to acquire and use, weighing such competing concerns as cost, ease of operation, efficiency, and image quality: HID lamps (metal halide and mercury vapor), and a bank of fluorescent tubes. Most of the alternative processes are much less sensitive than modern silver gelatin papers and must be printed by contact. The Sun The sun is one of the strongest sources of ultraviolet light but it varies greatly in intensity according to season, time of day, atmospheric conditions, and geographic location.
It is possible to print in direct sun or in open shade. Sun lamps A. HID Lamps. Build your own UV exposure box with fluorescent like lamps. A Treatise on Heliochromy: Or, The ... - Google Book Search. Bostick & Sullivan - Handcrafted Photographic Supplies. Jeffrey D. Mathias - Platinum Palladium Photo... Cyanotypes.com : news & info. To Transfer Images to Stone or Metal Usi...