Technical drawings on microfilm

Abstract

Both economy and the lack of storage space have induced projecting bureaux and industrial firms te file technical drawings on microfilm.
The purpose is to produce microfilms of which enlargements can be reproduced in the same quality as the original.
The requirements of uniform film density, the standards and rules for the reduction ratio and drawing techniques are reviewed.
Data on modern devices for processing and enlarging microcopies are shown in tables and the latest methods of enlarging are also dealt with.
Microfilmed technical drawings can be stored in various ways. Up-to-date storing methods can secure their rapid retrieval.