As Mars span towards its closest rendezvous with the Earth since the Stone Age on Wednesday, a group of French enthusiasts counted on off-the-shelf Internet technology to get that perfect snap to show their grandchildren. Although the team at the Ludiver observatory at La Hague, near Cherbourg on the Normandy coast, were mounting a continuous Mars-watch, they also hooked up a simple off-the-shelf webcam to their 60-centimeter optical telescope.