Image effect help?

hi,

I want to create the effect where you got loads of images or photos but when you look at it from a distance & hard it then looks like one big picture. so it loads of pics or phots that make up one big image.

I have not got a clue where to start with this one…can neone help?? or know any tutorials that can help me with this?

cheers peeps?? :asleep: