function opacity(id, opacStart, opacEnd, millisec) {
	    //speed for each frame
	    var speed = Math.round(millisec / 100);
	    var timer = 0;
	    var picdisplay = "block";
	    if (id == "bigpicture")
	        {
	            if (opacEnd != 100)
	                {
	                picdisplay = "none";
	                }
	            // 
	            document.getElementById(id).style.display = picdisplay;
	            document.getElementById("greyscale").style.display = picdisplay;
	                
	        }
	    //determine the direction for the blending, if start and end are the same nothing happens
	    if(opacStart > opacEnd) {
	        for(i = opacStart; i >= opacEnd; i--) {
	            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
	            timer++;
	        }
	    } else if(opacStart < opacEnd) {
	        for(i = opacStart; i <= opacEnd; i++)
	            {
	            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
	            timer++;
	        }
	    }
	}
	// shift opacity
	function shiftOpacity(id, millisec) {
	    //if an element is invisible, make it visible, else make it ivisible
	    if(document.getElementById(id).style.opacity == 0) {
	        opacity(id, 0, 100, millisec);
	    } else {
	        opacity(id, 100, 0, millisec);
	    }
	} 
	//change the opacity for different browsers
	function changeOpac(opacity, id) {
	    var object = document.getElementById(id).style;
	    object.opacity = (opacity / 100);
	    object.MozOpacity = (opacity / 100);
	    object.KhtmlOpacity = (opacity / 100);
	    object.filter = "alpha(opacity=" + opacity + ")";
		
	} 
	// blend image
	function blendimage(divid, imageid, imagefile, millisec) {
	// <a href="javascript:blendimage('blenddiv','blendimage', 'media/texts/photos_about/03aft.jpg',200)">Image 1</a>
	    var speed = Math.round(millisec / 100);
	    var timer = 0;
	    
	    //set the current image as background
	    document.getElementById(divid).style.backgroundImage = "url(" + document.getElementById(imageid).src + ")";
	    
	    //make image transparent
	    changeOpac(0, imageid);
	    
	    //make new image
	    document.getElementById(imageid).src = imagefile;
	
	    //fade in image
	    for(i = 0; i <= 100; i++) {
	        setTimeout("changeOpac(" + i + ",'" + imageid + "')",(timer * speed));
	        timer++;
	    }
	}
	// 
	function currentOpac(id, opacEnd, millisec) {
	//<a href="javascript:currentOpac('digicam3', 60, 300)">fade to 60%</a>
	    //standard opacity is 100
	    var currentOpac = 100;
	    
	    //if the element has an opacity set, get it
	    if(document.getElementById(id).style.opacity < 100) {
	        currentOpac = document.getElementById(id).style.opacity * 100;
	    }
	
	    //call for the function that changes the opacity
	    opacity(id, currentOpac, opacEnd, millisec)
	}