I've just gotten my first digital SLR (Rebel XTi) and don't have any lenses other than 50mm f/1.8. One of the things I would like to do is to photograph some of the events at our church - especially the upcoming baptisms and confirmations at Easter. I would have to be 20-40 feet away from the altar. I am considering buying a 28-135mm f3.5-5.6 IS as my "starter" lens until I can set aside the money for something better. Will this lens work well in a fairly well-lit church? If not, what lens ($500 or less) would you recommend?