Correct The Exposure: Multiply & Screen Blending Modes

Step 2: Create Shadows & Highlights Layers

I will duplicate the background layer twice and I will rename the layers: shadows, respectively highlights. To duplicate a layer, first select it in the layers dialog and than click on the duplicate layer button or just press Ctrl+Shift+D. To rename a layer just double click over its name, than edit and press enter to validate.

Next I will change the blending mode of the Shadows layer to Multiply and screen mode for highlights layer. The multiply mode always darkens the image, the screen mode always make the image lighter. More details on the blending modes available can be found into the GIMP manual.

You may wonder why do I need a layer like multiply, which darkens the image, since I already have a too dark one. Basically I have two reasons: I want to reduce the light of the sky a little bit and also because it will help me to give a more natural feel to the final result. Not all the time you will need both multiply and screen layers. It depends on your photo, so feel free to experiment.

Here it is the result when only the background and the shadows layers are visible, next only background and highlights and all of them visible in the third one.