On Wed, Jul 15, 2009 at 12:15, Ben Scott<[email protected]> wrote: > On Wed, Jul 15, 2009 at 1:00 PM, Kurt Buff<[email protected]> wrote: >> July 20th and July 4th are the two days I observe as truly worthy >> human events. > > What, no love for 12 April? ;-)
Well, it was a good day in 1945, but otherwise not so much. Heh. >> Best news of the week: NASA has found the lost tapes of the landing >> and walk, and will be restoring them. > > I had read that was a hoax[1]. I found a NASA press release saying > they are planning a release tomorrow (16 July), but careful reading > shows that it just says "greatly improved video"; mention of the > missing tapes is absent. I can't find conclusive information. :-( > > [1] > http://blogs.discovermagazine.com/badastronomy/2009/06/28/lost-apollo-11-video-tapes-found/ > [2] > http://www.nasa.gov/home/hqnews/2009/jul/HQ_M09-125_Newseum_Apollo_tapes.html > >> They were done with a high quality SSTV recording - apparently >> what the public has seen was standard resolution > > Not exactly, but close. The Apollo television cameras did not > resemble terrestrial TV systems due to technology limitations (e.g., > limited telemetry bandwidth, the need for the cameras to be both > light-weight and also survive vacuum and temperature extremes). The > frame rates and resolution differ. So for national TV broadcast, the > signal had to be converted. The conversion process used caused > significant quality degradation. (As I understand it, it wasn't much > more than pointing a regular TV camera at an SSTV monitor.) Then the > NASA copies of the original telemetry were "lost", so once more > sophisticated conversion was possible, there was no data to convert. > > SSTV = slow-scan television, i.e., TV at a frame rate slower than > normal. Apollo 11 was 320x220 pixels, at 10 frames/second, > non-interlaced. "Standard definition" NTSC is 30 frames/second, > interlaced to 60 fields/second, with 486 visible lines, and roughly > 640 horizontal dots. So there's nothing close to a simple conversion > ratio; sophisticated scaling and interpolation is needed to preserve > quality. > > -- Ben Got my news from here: http://science.slashdot.org/story/09/07/13/2342220/NASA-Has-the-Lost-Tapes but haven't cruised through all of the links... Kurt ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~
