1.  Open your image   (remove shadows on the background)

2. Lighten the image:  IMAGE ... ADJUST ... CURVES ... lighten

3. LAYER ... DUPLICATE ... LAYER ... OK

4. IMAGE ... ADJUST ... THRESHOLD

5. FILTER ... BLUR ... BLUR

6. Change the Layer Mode to Screen.  IMAGE ... MODE ... ???

7. Lower Layer OPACITY to taste.

8. LAYER ... FLATTEN IMAGE

optional:  use HISTORY BRUSH selectively