Give your window a name, and then reference this window name for all of your photos to open up in that window.
window.open("anywhere.html", "myWindowName", "width=150,height=210");
You can target that window in your HTML to load your images, or another url, in that window, if it already exists:
<A HREF="http://www.anywhere.com/" TARGET="myWindowName">Anywhere</A>
Can also do it this way: