diff --git a/app/models/album_setting.rb b/app/models/album_setting.rb
index 6215400..79565fc 100644
--- a/app/models/album_setting.rb
+++ b/app/models/album_setting.rb
@@ -12,7 +12,7 @@ class AlbumSetting
   before_save do
     if defined?(OrbitHelper::SharedHash) && OrbitHelper::SharedHash
       OrbitHelper::SharedHash['gallery'][:thumb_process_option] = self.thumb_process_option
-      OrbitHelper::SharedHash['gallery'][:resize_gravity] = self.resize_gravity
+      OrbitHelper::SharedHash['gallery'][:resize_gravity] = (self.resize_gravity.blank? ? 'Center' : self.resize_gravity)
     end
   end
 end
\ No newline at end of file
diff --git a/gallery.gemspec b/gallery.gemspec
index aaf8c79..7b4fc87 100644
--- a/gallery.gemspec
+++ b/gallery.gemspec
@@ -92,7 +92,7 @@ Gem::Specification.new do |s|
   s.license     = "MIT"
   s.metadata = {
     "_require" => "#{File.expand_path("../app/models/album_setting", __FILE__)}",
-    "global_hash" => "{resize_gravity: (AlbumSetting.first.resize_gravity rescue 'Center'), thumb_process_option: (AlbumSetting.first.thumb_process_option rescue 1)}"
+    "global_hash" => "{resize_gravity: ([AlbumSetting.first.resize_gravity, 'Center'].select{|s| s.present?}.first rescue 'Center'), thumb_process_option: (AlbumSetting.first.thumb_process_option rescue 1)}"
   }
 
   s.files = Dir["{app,config,db,lib}/**/*", "MIT-LICENSE", "Rakefile", "README.rdoc"]