I photographed this white Ranunculus bud on a black velvet background (above) and on a transparent white background generated using a light box (below). The white background was inverted to make the blackground black.
Actually, I like the monochromatic version best.
Random Ranunculus facts: every Ranunculus is different, no two buds are the same, even on the same plant; buttercups are part of the Ranunculaceae family.
Related image: Ranunculus Asiaticus.
View this image larger.