diff --git a/src/Phact/Orm/Fields/ImageField.php b/src/Phact/Orm/Fields/ImageField.php
index e01ebe5..ef74e57 100644
--- a/src/Phact/Orm/Fields/ImageField.php
+++ b/src/Phact/Orm/Fields/ImageField.php
@@ -128,13 +128,14 @@ public function sizePath($prefix)
         return $this->getStorage()->getPath($path);
     }
 
-    public function afterSave()
+    public function setValue($value, $aliasConfig = NULL)
     {
-        parent::afterSave();
-
-        if (!empty($this->sizes)) {
+        $createSizes = !(($value instanceof StorageFile) && $value->equalsTo($this->getAttribute()));
+        $attribute = parent::setValue($value, $aliasConfig);
+        if ($createSizes) {
             $this->createSizes();
         }
+        return $attribute;
     }
 
     public function deleteOld()
@@ -149,7 +150,6 @@ public function deleteOld()
         }
     }
 
-
     public function createSizes()
     {
         foreach ($this->sizes as $sizeName => $params) {
@@ -199,7 +199,6 @@ public function sizeContain(BoxInterface $box, $imageInstance)
         return $imageInstance->thumbnail($box, ManipulatorInterface::THUMBNAIL_INSET);
     }
 
-
     /**
      * @param $sizeName
      * @param $source ImageInterface
@@ -272,7 +271,6 @@ protected function getSizeBox(ImageInterface $image, $sizeParams)
         }
 
         return $box;
-
     }
 
     protected function preparePrefixSize($prefix)
@@ -280,7 +278,6 @@ protected function preparePrefixSize($prefix)
         return rtrim($prefix, '_') . '_';
     }
 
-
     public function getImagine()
     {
         if ($this->_imagine === null) {