1. After trying something with the option Overlay I started again doing this with the picture: 2. copy and paste it to a new layer 3. change the layer option to Overlay 4. invert the image 5. apply Gaussian blur 6. make one layer of it 7. adapt levels

It appeared to me the picture has become more greyish but the details are better visible. It's difficult to say what is better. So I thought, let's share it here. What do you think of it?

Jan-Carel