i want change footer in admin panel,

Zenphoto version 1.4.13 [5e8b3d9eb0] | License | User guide | Forum | Bugtracker | Change log | Server date: 2016-09-30 17:35:28

want to change this ^

Why? You are using an free and open source tool so this little footer should really not be that inconvenient. You would have to hack the core file admin-functions.php and the function printAdminFooter() if you really want this. You of course will have to re-do it after every update.