An introduction to the science & practice of photography (1888)
Jones, Chapman · London : Iliffe & Son · leaf 220
their visibility in excess of their chemical activity, and this is a guide for the light to be selected for developing, etc. Generally a dull, deep red is as safe as any light1 — a deep ruby glass, or this with cobalt glass in addition. Yellow is to be avoided, for the very aim of operations that… … ULTRA-VIOLET. VIOLET. BLUE. GREEN.YELLOW.REB. Fig. 46. stand for the Fraunhofer lines, and are lettered accord- ingly. The curves represent the intensity of action ; they rise to represent a larger effect, and fall to show a diminu- tion. Number 1 shows the visibility of the spectrum, number 2 the…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
