How to get a preloader to wait after loading images?

i'm using this

http://ift.tt/1Diw5Hc

I'm wanting this to be timed after the images have loaded ( i have some slow jquery that needs time to load the ajax call) So for example, after all images have loaded wait 10 seconds before displaying page?

Obviosuly i'm still wanting it to look as if it is loading something

Sam