Vixen 102mm f9 fluorite refractor Canon T3i DSLR at prime focus with 6x barlow Selection of best images stacked, process Registax 6 Images acquired 10-10-2013 just short of 1st quarter The spectral colors at bright edges near terminator are likely due to the 6x barlow. Images without this barlow show no color, as expected from the fluorite. Theophilus is about 100km wide, 3.2km deep, and the 4-peaked central mountain is about 1.4km high. It is estimated to be from 1-3 billion years old.