Openlayers image over standard map

I'm building a new mapping application. However, we need to be able to overlay a tif 开发者_如何学Pythonfile (for which we have coordinates to place it using OL bounds) over a map of the US/world. The tif file only covers about 20 kilometers or something so it's not very big. I so far have created a map element with just the tif file and I can pan/zoom etc on the tif, but I want to have the normal map behind it so that when the user pans out of the tif area, they see the regular map. Can anyone point me to some examples?

Take a look at Layer.Image object. Positions an image as a layer, and if you put that on top of a base map, it should do what you want.