The first picture is the original take of the flower.
By changing the saturation to the lower level you get
a Black and White look.
25% Saturation will produce the following:
75% Saturation will produce:
A great collection of purple flowers can be found in: http://www.tonyhowell.co.uk/purpleflowers.htm
The light condition of the picture below were on a cloudy day, 50% day light, when the green leaves, flower and soil were wet. I used my 18mm micro SLR to take this magnificent picture.