Supporters of manned spaceflight like to argue that the astronaut is more
effective than a robot. Well even if this was true the astonaut would need
to be not twice as effect or ten times or one hundred times but rather a
thousand times as effective to just get the same value as the robot. Lets
concede that the astronaut is twice as effective as the robot. That makes
the robot a better choice by a factor of five hundred times. Would the
Mars
pancam image be any better taken my an astronaut ?

If you consider that the entire distance driven by both Lunkhod's and Mars
Pathfinder
was less than the shortest LRV traversal on Apollo 15, and that the total
volume of samples returned by the successful Soviet Lunar return mission
probes had a mass about equal to the Apollo 11 contingency sample, then I
would imagine that an astronaut is much more than two times as effective as
a robot. Maybe 100 times, for the right sort of mission. (Field geology.)