[i speak in math]

I picked up some used vivitar extension tubes to go with my smc 50mm f/1.4 on my K20D. So for a total of $120 for the lens and extension tubes, you can go 1:1 macro. Plus you will have a beautiful 50mm for many other situations. No need for a dedicated macro lens. I usually use my lp120 to light the shots since stopping down to f/16 and using the tubes has quite a bit of light loss.