One quick technique for enhancing the exposure latitude of an image and bringing out the detail is applying 50% gray to a new layer. This Adobe Photoshop technique may allow you to enhance the highlight and shadow information contained in the image. Naturally, this won't work on all images with this quick fix. This technique will work with any program that supports layers and blending modes.
1. Open the file. Choose File --> Open --> Enter the image name.
2. Hold the Ctrl Key down and hit the + key a few times to zoom in the image to a size you need to work with.
3. Hold the Ctrl Key down and hit the J key once to create a new layer. Select the new layer to work with.
4. Choose Edit --> Fill and set set to 50% gray (A), color dodge (B) and 50% opacity (C). Click OK. (Figure 1 & 2)
5. Change the blend mode (B) and the opacity (C) to fit your needs.