Dennis Wingo: Status mid day August 29, 2013.
Not running tapes all day today, other paperwork to get through. Did four tapes this morning and it is getting interesting juggling the tapes. An obvious principle for you folks who have been reading this is to maximize the number of images while minimizing the amount of tapes to read and thus head wear. With 477 tapes, Lunar Orbiter V has 60% more tapes than any of the other missions and thus you would think there is a lot of overlap and there are.
Some of the overlap is easy as all you have to do is look at the sequence numbers and the GMT time on a tape to see when two tape machines were running at the same time. Thank God everything was in GMT! However, there are times when a tape would get changed in the middle of a read out (image transmission) from the spacecraft. Thus we lose framelets (parts of an image). You can see some of these losses today when you go to the www.lpi.usra.edu site. By the way, this project would have been impossible without all of their pioneering work to preserve LO images in the 1990’s.
So, what we have after running the Woomera tapes are times, as I have stated before, of overlaps and sometimes the Goldstone tape would stop earlier or run longer than the Woomera tape. Today is one of these times in that we have multiple instances of this overlap that allows us to recover framelets that might otherwise be lost. It causes a headache in our accounting and image runs downstream as we usually do the work by a tape and it is a pain in the rear to merge multiple tapes into an image. Austin had been doing a lot of that work on the backend processing but now with my note leaving here I can not only communicate what is going on to you the reader, this is helping our team internally as I can lay out what I have done with individual tapes and how that integrates into the larger stream of assembling the images.
This is the case today. Here are the tapes run and the juggling between images and tapes.
G5-031, partial capture LOV-068H, 067H, complete capture 066M
G5-032, partial capture LOV-069M, 070H
G5-033, partial capture LOV-070H (completes image and overlaps with W5-139), partial capture 068M (completes image and overlaps with W5-140)
G5-034, partial capture LOV-072H (completes image and overlaps with W5-029), partial capture 070M (completes image and overlaps with W5-030)
The good news is that for G5-033 and 034 I only had to run about 5-10 minutes of each tape rather than 40+ minutes each. This saves enough head life for another tape!
Official website of the Lunar Orbiter Image Recovery Project (LOIRP)