NSSDCA ID: PSPA-00115
Availability: At NSSDC, Ready for Offline Distribution (or Staging if Digital)
Time span: 1965-07-14 to 1965-07-14
This data set contains several types of enhancements of the 21 pictures plus 21 lines of picture 22 returned by the television experiment. The photographs are on 4- by 5-in. negative film sheets. The following types of enhancements are available: type A -- Aeronautical Chart and Information Center (ACIC) air brush renditions (an interpretive rendition of what the surface of Mars may look like), type B -- a calibrated and geometrically corrected version enhanced in contrast, type C -- the same as B, but also sharpened, type D -- a negative version of the calibrated, enhanced picture in the original picture format, type E -- a calibrated, contrast-enhanced version in the original picture format, type F -- same as E version, but also sharpened, type G -- "fluctuation plot" in which smooth areas are rendered as dark and locally rough areas are rendered as light. Calibration removes the sensor properties from the image, i.e., vidicon plate shading. Sharpening helps to delineate the crater edges. Variance plots are basically for photometry purposes. The pictures are numbered 1B, 1C, etc., denoting picture order number and enhancement type as designated above. Each of the first 16 pictures taken by the vidicon has been enhanced by the methods described. The ACIC airbrush renditions combine two overlapping pictures on one 4- by 5-in. film sheet. There are therefore eight of these numbered 1, 2A, 3, 4A, etc. Picture no. 1 was enhanced to discern haze. Since the picture element (pixel) range was small in pictures 17 to 22, the pixels have been linearly stretched to present some contrast in the image. The low contrast discernibility in the negatives, however, results in pictures of negligible value. In a separate enhancement of picture no. 1 (designated as 1H), pixels were stretched and lightened only in the haze portions in order to indicate contrast in this phenomenon. Reproductions and further discussion and interpretation of these television pictures are presented in Mariner Mars 1964 Project Report, Television Experiment, Part I, Investigators' Report, of JPL Technical Report 32-884, "Mariner IV Pictures of Mars," by Robert B. Leighton, et al., 1967.
Questions and comments about this data collection can be directed to: Coordinated Request and User Support Office
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Robert B. Leighton | General Contact | California Institute of Technology |