The Viking landers were not blind, they just took ages to record and send a single still image.
http://www.msss.com/mars/pictures/viking_lander/12a168corr.jpg
http://www.msss.com/mars/pictures/viking_lander/22a158corr.jpg
http://photojournal.jpl.nasa.gov/spacecraft/Viking%2BLander%2B1
http://nssdc.gsfc.nasa.gov/imgcat/html/mission_page/MR_Viking_2_Lander_page1.html
What they said at the time was a Martian could walk right up to a Viking lander, and the lander would never know,
