[gbog]

Since when it is ok to suppose visitors know to click the escape key to go back. And where is the link to go up to the gallery. I had to mess with the url or I was gone for a long back button session. Morevoer it is very slow.

Just to add some negativeness to the generaly positive comments here.

[uptown]

By "go back" i'm assuming you're referring to closing a full-size image. I've found three ways they can do this. They can press ESC. Click the image itself. Or click in the negative space surrounding the image excluding the "Previous" and "Next" regions.

Doesn't really seem like a huge issue since there are multiple ways to accomplish the objective, though I suppose a small "X" could be added if you wanted a visual cue.