I bought it months ago, so I can't really remember. If not mistaken, it's around $60-$75. If you have a good tripod, I don't think you need it, unless you take a lot of nite shots.Originally posted by tomshen
How much u paid for it?
USM stands for Ultra Sonic Motor, a term used by Canon, while HSM is the Sigma's term for Hyper Sonic Motor.Originally posted by kylelam77
sigh... dun know when i will be able to do that. My oly only allow up to 16s exposure. if i allow that long an exposure time, i would be seeing lotsa tiny and green ufos in my pic liao. btw, can someone explain to me what those usm or hsm lenses are ?