Make posts popup like pinterest

I have searched and tried several plugins but I cannot seem to find a way to have posts pop up like pinterest does it.

What I need exactly is to have someone click on the thumbnail from the homepage and have the fullsize image open up in a lightbox, as well as everything else I configured on single.php. However, I would like them to popup and have the user be able to scroll just the popup while the main page is static behind it (just like pinterest).

Anyone have any suggestions as to how this could be accomplished?