Imagine a flower arrangement on a table with a trellis about 3 feet behind. How can I get the entire arrangement tack sharp, but blur the trellis? I use a Canon XTi, have a 60mm, a 28-135mm, and the kit 18-55mm. If I use a smaller aperature, then the trellis is in focus. If I use my 60mm with a larger aperature, then only one flower is in focus and everything else (including the rest of the arrangement) is blurred. Is the arrangement too close to the trellis? Any suggestions?