Thanks everyone!
This is 100% natural sunlight.
This water lily is one of my favorite flowers to photograph.
I have had this plant for two years now and was very happy to get it to recover after almost dying last winter. The yellow pollen in the middle glows with the light from the sun and they only stay open when direct sunlight is shining on them, otherwise the flower closes up.
The 100 APO with the 36MP sensor renders detail on the pollen crystals on the stamens.
Thanks David at Leitax, the Nikon replacement mount is very solid with no play.
It will be more solid on my 1ds3 too as I find the Nikon to Canon adapters to be more solid than Leica to Canon.