At 10 a.m. Saturday at Churchill Downs, the sun is shining and the clouds are moving out. The National Weather Service is calling for a high of 70 under partly cloudy skies when the Kentucky Derby is run at approximately 6:04 p.m.For 90 minutes before the first post, the infield crowd is noticeably smaller than in past years. There are numerous security precautions which seem to have kept some infield regulars at home.Two horses have been scratched from the Derby, Buddha and Danthebluegrassman. This leaves a field of 18 to go postward in the 128th Derby.There are a few other scratches from the card: Beverly Greedy in the first; Penny Marie and City Fair in the seventh; Shah Jehan in the 10th and Storm Dancer, Voodoo Lady and Berry Springs in the day's last race, the 11th. The Derby is the ninth race on the card.