I am using a 300D with Sigma 18-125 f3.5-5.6 DC, btw the lens says its minimum focusing distance is 50 cm.
I found that focusing on distant subject I get sharp and clear picture. However, focusing closer objects (within 2 m or so), at 100% magnification the image is blurry. Suspected motion blur but tripod and flash doesn't help. Raising F number to 8 or 16 doesn't help too. Ironically I find my old camera Sony DSC-F717 is sharper, be it near or far.
What's wrong? Camera focussing problem? Or lousy lens?