- Shadows are more complex than you would think, and you can't normally turn a shadow into a mid-tone simply by brightening it up.
- Merge with Retouching Shadows.
How to Edit Shadows
- The most accurate way to edit shadows is using Shadows & Highlights (Menu> Image> Adjustments > Shadows & Highlights), however this is destructive and there is not an Adjustment Layer which does the same thing non destructively. However, you can convert the image to a Smart Object and apply this as a Smart Filter.
- How to Remove Shadows from a Photo in Photoshop - photoshopCAFE