// IMAGE NAVIGATOR ROUTINES

    function showImage(){
        
        if ((!photos) || (photos.length < 1)){
            var noImage = document.getElementById("noImage");
            var imageGallery = document.getElementById("imageGallery");
            var imageTd = document.getElementById("imageTd");
            var previous = document.getElementById("previous");
            var next = document.getElementById("next");
            var imageNum = document.getElementById("imageNum");

            imageGallery.style.display = "none";
            noImage.style.display = "block";
            imageTd.style.borderWidth = "1px";
            imageTd.style.borderStyle = "solid";
            imageTd.style.borderColor = "#bfbfbf";
            previous.style.display = "none";
            next.style.display = "none";
            imageNum.style.display = "none";

            return;
        }
        
        var image = document.getElementById("imageGallery");
        if (!image)
            return;;
        image.src = photos[currentIndex];
        var span = document.getElementById("imageNum");
        if(!span)
            return;
        span.innerHTML = "Photo " + (currentIndex + 1).toString() + " of " + photos.length.toString();        

    }

    function previous(){
        if (currentIndex > 0){
            currentIndex--;
            showImage();
        }
    }
    
    function next(){
        if (currentIndex < (photos.length - 1)){
            currentIndex++;
            showImage();
        }
    }