|
The Ca K plates have been stored in paper envelopes housed in wooden cabinets. The large collection of these plates exceeded the drawer space and some groups of plates were stacked in boxes. The more vulnerable groups have been relocated. The wooden boxes emit gasses which are harmful to the photographic emmulsion and a part of the project is to move the plates to more inert archival boxes. The top image to the left shows a bank of drawers, most of which on the left are empty. Starting about where the one is pulled out, the drawers contain Ca K plates from the 1950's era. The lower image gives a closeup of the drawer with one plate envelope pulled out. The discoloration of the paper is partly from its higher than desireable acid content and from the action of the wooden box walls.
The bottom figure shows the storage of the plates obtained by Prof. Robert Leighton between 1959 and 1964. These include some of the finest examples of spectroheliograms available. Many were published in 1966 by The Carnegie Observatories in a volume authored by Dr. Alan Title and entitled "Selected Spectroheliograms".
|
|
|