BS 5525:1977

Foreword
Cooperating organizations
Specification
1. Scope
2. References
3. Definitions
4. Originals suitable for microfilming
5. Microfilm
6. Density
7. Resolution
8. Quality of microfilm
9. Procedures for microfilming
10. Sequence and numbering
Appendices
A. Measurement of background density
B. Resolution test
C. Checking bow in microfilm
Tables
1. Resolution
2. Paper sizes and reduction ratios
Figures
1. Outer margin
2. Test target
3. Use of multiple frames for microfilming originals
    not more than 841 mm wide and more than 1189 mm long
4. Use of multiple frames for microfilming originals
    more than 841 mm but not more than 1189 mm wide
5. Use of multiple frames for microfilming originals
    more than 841 mm wide and more than 1189 mm long
6. Template for checking bow

Sets out requirements for preparation and microcopying in black and white of topographical maps and plans, either for the production of prints or for viewing. Dimensioned drawings, the subject of BS 4210, are excluded. Sets out procedures for maintaining and checking the reproducibility of microfilm images and the qualities of negatives on 35mm silver microfilm from published maps or originals prepared in accordance with this standard. Background density, resolution and procedures for assessment are also covered.