Sunlight filtering through the tree-crowns produces a dazzling patchwork of shadows and reflections. I prefer cloudy days, particularly after rain, when contrasts are subtle and colors intense. Always use a tripod for low-speed exposures.
When shooting against the sun, the light-meter may be fooled by the stronger light coming from behind the main subject. Check the reading close to the main subject, and then step back for a shot, using the same reading. Or open the diaphragm 1 or 2 points more than indicated by the light-meter for a longer-distance exposure reading.
Always use a Skylight or UV filter to protect your lenses, but when you need to clean them, first remove excess dust with a soft brush, and then polish them with special Kodak Lens Cleaning Paper, using light circular movements. To remove grease from lens surfaces, use rectified benzene, and discard the lens cleaning paper after each use.