@ -759,7 +759,8 @@ function hook_islandora_derivative_alter(&$derivatives, AbstractObject $object,
'dateLastModified' => NULL,
'dsid' => NULL,
);
if (empty(array_diff_key($ds_modified_params, $mask))) {
$param_diff = array_diff_key($ds_modified_params, $mask);
if (empty($param_diff)) {
$derivatives = array();
}