1) Open both the b/w and the colour version of the photo, drag the b/w version on top of the colour version using the move tool – hold down the Shift key to get the b/w pinned to the exact centre of the colour image. As they are esentially the same picture, they will register exactly on top of each other.

2) Using your favourite selection tool, make a selection of the wall. As the guitar has a very sinuous shape, I decided to try the pen tool for this and create a path which I converted to a selection (Cmd/Ctrl-Enter). (I won’t attempt to explain the pen tool. I hardly understand it myself.) Add a layer mask to the b/w image while the wall is selected, this should let the wall shine through from the colour version.

3) Although the guitar is still white (and should be), the side panels would reflect a certain degree of colour. Therefore, I made selections of the two sections of the side panel (again with the pen tool, but the Quick Selection tool or the Tragic Wand would work nicely here too) and paint them in with a gray tint (I simply used a black brush at 20% opacity) to reveal SOME of the colour from the below layer.

4) Just a little enhancement – I duplicated the top layer (Cmd/Ctrl-J), made a selection of the hole in the body and added a mask to just show the label inside and changed the blending mode of that layer to Screen to brighten it.

5) Optionally: I created a Hue/Saturation adjustment layer above the background, checked the Colorize option and chose a light bluish hue. This turns everything that is visible from the background layer into another colour – it doesn’t actually show up in the version above.

It’s actually a fairly quick job. The selections take a bit of time, but the beauty of doing them with the pen tool is that you can actually save your selections (as paths) with the image. Hope it inspires someone!

Henrik, I like how you added a tint of color to the guitar side panels. Great move there.