Comparison between original image and final rendering
1. After opening the original gray image, copy the layer.
2. Duplicate the layer and change the blending mode to Soft Light.
3. After combining the layers, because the film is extremely gray, repeat the above steps. 2nd soft light
4. Select the menu: Filter > Others > High Contrast and keep the value at 50
5. Select the menu: Filter > Sharpen > USM Sharpen
6. Merge the layers and you’re done!