3 ms·

www.jpl.nasa.gov/news/fact_sheets/viking.pdf UHF 1Kb/sec to the orbiter, also could use S-Band direct to earth at a lower bandwidth. The orbiter could buffer 4

www.jpl.nasa.gov/news/fact_sheets/viking.pdf UHF 1Kb/sec to the orbiter, also could use S-Band direct to earth at a lower bandwidth. The orbiter could buffer 40 Mb. Not sure how fast its link to the DSN was. ed: 16Kb/sec in there too. Example DSN doc: ipnpr.jpl.nasa.gov/progress_report2/42-33/33C.PDF My memory was everything was first shown grayscale, and then color. Not sure if that was a ground processing thing or the lander/orbiter sent two streams. Maybe the orbiter buffered the deeper bits and sent 8bit for near-realtime enjoyment.

dwc 12y ago
(Educated) guess: the monochrome image was simply the first wavelength band that came down. The later color image could be composed after the other bands were received.
- ConceptJunkie 12y ago
  I don't know if a single wavelength monochrome image would look very good, especially if it were, say, blue, instead of red. Creating the color images was a lot harder than we might imagine, in a world where Photoshop does CMYK separations at the click of a mouse. Since I'm old enough to remember the Viking landing, they first reported on TV when the first color pictures were processed that Mars had a blue sky just like Earth. However, this was quickly corrected once the color pictures were correctly calibrated. Of course, interestingly enough you can see blue in the Martian sky at dusk or dawn.
  - dwc 12y ago
    Of course it depends on the wavelength, but single band images look a lot like any grayscale image. It's typically only when different single-band images are compared side by side that the differences really jump out. Which is, of course, why they bother with multiple bands. I worked on the lunar reconnaissance orbiter camera, and was involved with image processing and calibration for the wide angle camera, which is multiband (5 bands in visible, 2 in UV).
ak217 12y ago
A 40 MB buffer on an interplanetary spacecraft in 1975 is pretty impressive.
- deleted 12y ago
  [deleted]
- kalleboo 12y ago
  Looks like the buffer was on tape - it would record at the speed of acquisition, and then when it was time for transmission it would spool the tape at whatever rate was appropriate for the quality of the radio link. And it's small b, so 5 Megabytes on the tape.

dwc 12y ago

(Educated) guess: the monochrome image was simply the first wavelength band that came down. The later color image could be composed after the other bands were received.

ConceptJunkie 12y ago
I don't know if a single wavelength monochrome image would look very good, especially if it were, say, blue, instead of red. Creating the color images was a lot harder than we might imagine, in a world where Photoshop does CMYK separations at the click of a mouse. Since I'm old enough to remember the Viking landing, they first reported on TV when the first color pictures were processed that Mars had a blue sky just like Earth. However, this was quickly corrected once the color pictures were correctly calibrated. Of course, interestingly enough you can see blue in the Martian sky at dusk or dawn.
- dwc 12y ago
  Of course it depends on the wavelength, but single band images look a lot like any grayscale image. It's typically only when different single-band images are compared side by side that the differences really jump out. Which is, of course, why they bother with multiple bands. I worked on the lunar reconnaissance orbiter camera, and was involved with image processing and calibration for the wide angle camera, which is multiband (5 bands in visible, 2 in UV).

ak217 12y ago

A 40 MB buffer on an interplanetary spacecraft in 1975 is pretty impressive.

deleted 12y ago
[deleted]
kalleboo 12y ago
Looks like the buffer was on tape - it would record at the speed of acquisition, and then when it was time for transmission it would spool the tape at whatever rate was appropriate for the quality of the radio link. And it's small b, so 5 Megabytes on the tape.