Creating graphics canvases and raising/lowering them

[HydroBob]

I have 6 graphics that I want to put onto a canvas (thumbnails of original images).
I want to create this canvas when I press a button. After this canvas is
created I want to be able to zoom in on any of the 6 smaller images by
clicking a mouse button (bring to the top the original large image), then be able to
return to the thumbnail version by clicking a mouse button on the large image.

How do I go about doing this? I have been able to get the thumbnails on a
canvas, click on one of the thumbnails and bring up the large version but it
always justs overlays on the thumbnail canvas (can still see the edges of
the thumbnails). I can't seem to be able to raise/lower canvases.

I have been beating my head against the wall trying to figure this out. I am
new to tcl/tk and would appreciate any help you can give me.

Thanks!!