is my lens crappy or is it me?

[chip]

Try to step down to maybe f11 and it should be sharper. Are you using a 580EX2? What flash are you using? You said "There is almost no ambient light in the studio". If the studio is completely dark it may need some light for the AF to work. Although from looking at the picture it does not seem to be a focus issue. Chip

 

[cfusionpm]

It's not really going to help. The kit lens on the XSi just isn't very good. Its a slight bit better than the old non-IS 18-55s that were on the XT/XTi, but none of them are all that good. They use poor, cheap components and as a result, their optics are sub-par. I managed to get some decent shots with the kit lens on my XTi, but they were never as crisp or clean as the 17-85 f/4-5.6 IS, and nowhere near as close as the 17-55 f/2.8 IS. For shots like the example above, your best bet is to replace that cheap glass, as the technique seems just fine. If you're in the market for the 17-85, I've been meaning to sell it ever since I got the 17-55.

 

[kkamin]

Try to step down to maybe f11 and it should be sharper. Are you using a 580EX2? What flash are you using? You said "There is almost no ambient light in the studio". If the studio is completely dark it may need some light for the AF to work. Although from looking at the picture it does not seem to be a focus issue. Chip

I think there is enough light for the focusing. I'm focusing from the modeling lamps in the strobes (200 watt bulb going through a 5' softbox set about 2 feet above them.)