Dear Stjepan Dekanic, I recently did a study looking at canopy cover with a very cheap and simple method. I don't know if it would be accurate enough for what you need, but what we did was take images of the canopy at a fixed height above the ground (we used 2m) with a regular digital camera (no special lens). We then analyzed the images for perent canopy cover using ImageJ, free public domain software from the National Institute of Health (you can download it at <http://rsb.info.nih.gov/ij/download.html>. With the program we basically converted the images so that each pixels was all classified as either sky or canopy and then simply calculated the percentage of pixels that were canopy (percent canopy cover). If you are interested in knowing more let me know and I can share the detailed instructions for the procedure. The advantage is that it does not cost anything beyond the cost of the digital camera; the disadvantage is that it is not as precise as having the fisheye lens set-up. =20
Best of luck to you, =20 Joie L. Goodman, M.S. Project Field Botanist Center for Tropical Plant Conservation Fairchild Tropical Botanic Garden 11935 Old Cutler Rd. Coral Gables, FL 33156 Office: 305-667-1651 x3436 Cell: 954-734-0477 =20
