This pic was taken about 2 years ago on a mayfair my dad had, that oil was leaking all over the diff as you can see!!

As for the photos, all i can say is don't get too close without the makro.. and if there is more light on one side than the other, get the light reflecting into the lense, small lense cameras need masses of light.
And what you can try doing to determine where the leak is definately coming from, is clean the underside of the engine, sump, diff, CV joints etc with some sort of oil remover, then check it a few hours/days later to see where the fresh oil has ran.