All of these were taken with the Nikon kit lens 18-55mm and a set of close up filters that screw on the front of the lens. I had them left from my old film camera and lo and behold they fit the lens I have now, so I have been using them for really small flowers and any bugs that come into frame.
As far as sharpness, considering the lens, the filters and being hand held, these are not bad (I guess), I know if I was not so lazy (tripod), I could do better. I was lucky to have good light this day. They were shot at f16 (with the filters DOF is microscopic with the lens opened up) and I still had a fast enough shutter speed - sort of.
Wendy