I have a skeleton watch which has a glass face in the front and back so the watch is see through. I would like to remove the background behind the watch without removing the glass of the watch. The watch is see through at the areas where the movement is not present.
Are you able to post an example. It sounds like you will need to mask the area then paint in the glass reflections, but without seeing the image it is hard to comment further.
Post an example. Transparencies typically involve some channel calculations and not just selections.
If the background you want to eliminate is white -- whiter than any part of the watch mechanism -- you may consider the Layer Style / Blend If command with a transparent layer below the watch. Moving the top right slider gently left should eliminate the white background.