Our white flowering magnolia was in peak form on a sunny morning. Camera was a Nikon D90; lens was the Nikon 18-55mm AF-S VR DX. I used a Nikon Circular Polarizer. (The Nikon polarizer is expensive as filters go, but I use one 77mm filter with step-up rings so that I have one filter for all lenses.) Post-processing in Aperture was auto-enhance, followed by increasing tonal range in the Levels tool, plus some tweaking of saturation, definition, or shadows. All images are ISO 100, with circa f/6, circa 1/160 sec exposure.