In the late 70's, nasa tried to hide alien artifacts. When you try to download this Apollo 17 spacecraft picture, you get a complete low-res photography: http://www.lpi.usra.edu/resources/apollo/frame/?AS17-M-2806. If you want to get the hires print photography, you get this one: http://www.lpi.usra.edu/resources/apollo/images/print/AS17/M/2806.jpg. Apollo 15 used 4*5 inches silver negatives. No flight problem or scanner distorsion can justify such a mess. A natural negative problem is this one; end of a magazin. http://www.lpi.usra.edu/resources/apollo/frame/?AS15-M-0113. In late 70's nasa couldn't anticipate public internet ,so , it's a nice bad disinformation attempt.