The Average Picture Level of Some Television Films

Daan M. Zwick

Average picture level (APL) of a film is the integrated optical density or transmission of a full picture frame. Its television correlate is the video signal level averaged over a full frame. This paper reports measurements of samples of television newsfilm, spot commercials and program films. A wide range of APL is reported in all types of films. In terms of optical density, APL of television entertainment films varied from 0.4 to 1.9, with a mean of 0.9 for ten different programs. (The SMPTE Color Reference Test Film has a mean APL of 1.3.) Newsfilm had less variation in APL, ranging from 0.6 to 1.9, with a mean density of 1.1. Film commercials ranged widely in APL, from 0.3 to 2.0. The mean density of 1971 commercials, 0.7, is lower than that of programs or news, and is noticeably lower than it was in 1969. Thus, commercials are noted as having higher APL than programs or newsfilms, and that difference has increased in the past two years.

Print ISSN
Published
1973-03
Content type
Original Research
DOI
10.5594/J07685