Practical Considerations in Granularity Measurements.
Final rept. Dec 74-Apr 75,
AIR FORCE AVIONICS LAB WRIGHT-PATTERSON AFB OHIO
Pagination or Media Count:
RMS granularity measurement techniques and problems are examined using Kodak 3414 film as the test specimen. The flashed wedges with pelloids on the film backing increased the RMS granularity as compared to an equivalently exposed 3414 film with pelloids removed. Proper microdensitometer focus is important for obtaining the best density versus position trace data, and thus, the best RMS granularity figure. Computer routines to eliminate density wedging due to nonuniform exposure and spikes caused by scratches or foreign particles improved the reliability of the RMS granularity calculation. The probability density distribution of the density data for a flashed specimen with pelloids removed is very near a Gaussian density distribution after data imperfections are removed. Author