Foxy Bob,
With a working distance of just 30cm then I am quite amazed at the zone of sharpness you have achieved. Your idea with the reflective part of the brolly ie making a softbox is excellent. As we found when adding a silver brolley behind the white one it frees up a flash unit.
Dabbling with manual flash now !!!
With this quality of pic, and dark wet days in front of us, it will soon be my turn to set a challenge.
Don