function ChangeImage(){
	bannerImageSmallCount = 51;
	bannerImageLargeCount = 24;
	path = "http://www.calvarysandiego.com/CCSD/images/header/banner_image_";
	
	incrementSmall = Math.floor(Math.random() * bannerImageSmallCount);
	incrementLarge = Math.floor(Math.random() * bannerImageLargeCount);
	
	// change the two banner images
	if (document.banner_image_small) {
		document.banner_image_small.src = path + "small_" + incrementSmall + ".jpg";
		document.banner_image_large.src = path + "large_" + incrementLarge + ".jpg";
	
		// change images periodically
		setTimeout("ChangeImage()", 30000);
	}
}