diff --git a/src/viewer.js b/src/viewer.js
index e05bbba8..971eb9d7 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -2735,11 +2735,9 @@ function resizeViewportAndRecenter( viewer, containerSize, oldBounds, oldCenter
 
     // We try to remove blanks as much as possible
     var worldBounds = viewer.world.getHomeBounds();
-    var aspectRatio = worldBounds.width / worldBounds.height;
-    var imageHeight = 1 / aspectRatio;
-    var newWidth = oldBounds.width <= 1 ? oldBounds.width : 1;
-    var newHeight = oldBounds.height <= imageHeight ?
-        oldBounds.height : imageHeight;
+    var newWidth = oldBounds.width <= worldBounds.width ? oldBounds.width : worldBounds.width;
+    var newHeight = oldBounds.height <= worldBounds.height ?
+        oldBounds.height : worldBounds.height;
 
     var newBounds = new $.Rect(
         oldCenter.x - ( newWidth / 2.0 ),
diff --git a/test/demo/collections/index.html b/test/demo/collections/index.html
index b6aca4a1..46b4e7f2 100644
--- a/test/demo/collections/index.html
+++ b/test/demo/collections/index.html
@@ -15,6 +15,10 @@
                 margin: 0;
             }
 
+            .openseadragon1.small {
+                width: 50%;
+            }
+
             .openseadragon-overlay {
                 background-color: rgba(255, 0, 0, 0.3);
             }
diff --git a/test/demo/collections/main.js b/test/demo/collections/main.js
index b2c7eeb8..01f7229d 100644
--- a/test/demo/collections/main.js
+++ b/test/demo/collections/main.js
@@ -116,6 +116,12 @@
             }
         },
 
+        // ----------
+        toggle: function() {
+            var $el = $(this.viewer.element);
+            $el.toggleClass('small');
+        },
+
         // ----------
         basicTest: function() {
             var self = this;