1. Open the file
2. Make a copy of the background (Cmd or Ctrl J) and set the blend mode on Multiply (darken) or Linear burn.
3. Add a mask to the top layer and select the 'black to white' gradient.
WHITE REVEALS, BLACK CONCEALS
Search ResultsIf the effect is the strong you can lower the Opacity of the layer
Just try it out.
Easy and quick.