Analysis and Measurement of Distortion in Variable-Density Recording
Several types of non-linear distortion in variable-density recording are discussed and methods of measurement outlined. The two-frequency intermodulation method is described. Mathematical and experimental relationships between per cent intermodulation and per cent harmonic distortion are established. The intermodulation method is applied to film processing for the determination of optimal negative and positive densities and overall gamma. Variances of these parameters from those indicated by classical sensitometry are traced to halation in the emulsion and to processing irregularities. The uses of special anti-halation emulsions appear to reduce residual distortion effects and tend to bridge the gap between intermodulation and sensitometric control values.
- Print ISSN
- 0097-5834
- Published
- 1939-06
- Content type
- Original Research
- DOI
- 10.5594/J11990