diff --git a/boards/static/js/image.js b/boards/static/js/image.js
--- a/boards/static/js/image.js
+++ b/boards/static/js/image.js
@@ -38,11 +38,15 @@ function addImgPreview() {
         var thumb_id = 'full' + el.find('img').attr('alt');
 
         if(!$('#'+thumb_id).length) {
-            var img_w = el.find('img').attr('data-width');
-            var img_h = el.find('img').attr('data-height');
+            var imgElement= el.find('img');
+
+            var img_w = imgElement.attr('data-width');
+            var img_h = imgElement.attr('data-height');
 
-            var win_w = $(window).width();
-            var win_h = $(window).height();
+            var win = $(window);
+
+            var win_w = win.width();
+            var win_h = win.height();
             //new image size
             if (img_w > win_w) {
                 img_h = img_h * (win_w/img_w) - margin;
@@ -54,8 +58,8 @@ function addImgPreview() {
             }
 
             var img_pv = new Image();
-            $(img_pv)
-                .addClass('img-full')
+            var newImage = $(img_pv);
+            newImage.addClass('img-full')
                 .attr('id', thumb_id)
                 .attr('src', $(el).attr('href'))
                 .appendTo($(el))
@@ -69,16 +73,15 @@ function addImgPreview() {
                 .mousewheel(function(event, delta) {
                     var cx = event.originalEvent.clientX,
                         cy = event.originalEvent.clientY,
-                        i_w = parseFloat($(img_pv).width()),
-                        i_h = parseFloat($(img_pv).height()),
+                        i_w = parseFloat(newImage.width()),
+                        i_h = parseFloat(newImage.height()),
                         newIW = i_w * (delta > 0 ? 1.25 : 0.8),
                         newIH = i_h * (delta > 0 ? 1.25 : 0.8);
 
-                    $(img_pv).width(newIW);
-                    $(img_pv).height(newIH);
+                    newImage.width(newIW);
+                    newImage.height(newIH);
                     //set position
-                    $(img_pv)
-                        .css({
+                    newImage.css({
                             left: parseInt(cx - (newIW/i_w) * (cx - parseInt($(img_pv).position().left, 10)), 10),
                             top:  parseInt(cy - (newIH/i_h) * (cy - parseInt($(img_pv).position().top, 10)), 10)
                         });
@@ -89,11 +92,10 @@ function addImgPreview() {
                     addClasses: false,
                     stack: '.img-full'
                 })
-        }
-        else {
+        } else {
             $('#'+thumb_id).remove();
         }
         //prevent default
         return false;
     });
-}
\ No newline at end of file
+}