With 50x optical zoom you would always want to try and get the subject as close as possible. I tried something similar on last weekend. Flies, spiderwebs, bees, butterflies and what not. Its amazing when you get to see the minute details of these little creatures. All of these photos have been shot using shutter priority mode to eliminate any camera / hand shake. The light was good so the ISO was always set below 400.
Most of the above shots were taken early in the morning. Usually that's best time when these insects are out looking for food and if you sight them, they can stay unmoved for long time on flowers, leaves and branches. Do share your views :-)
I've been using Canon right since I started with Photography and I also always recommend others to Buy Canon :-).