Photoshop :: Make Grey Background Visible When Zoomed In

So when you're zoomed out, you can see a grey background around your canvas. But when you're zoomed close enough, so that your canvas is bigger that your screen, you can't see that grey background, since the canvas become the borderline of your working space.
 
But is there a way to make that grey background visible even if i'm zoomed in?
 
Example: I'm drawing grass and I would like that my brush strokes begins outside of the box, while being zoomed in.