This is a picture that has a blown out sky. It would be better to spend a small amount of money to get a graduated neutral density filter and get this kind of shot right in the camera. Without doing that, we can use digital post-processing to imitate the effect of an ND filter and make the sky less overpowering.

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The first step is to duplicate the image onto a new layer by using ‘Layer’ > ‘Duplicate Layer’. This will be the layer with a darkened sky that matches the ground better. The best way to darken the sky is probably to use the ‘Image’ > ‘Adjustments’ > ‘Shadow/Highlight’ tool (in Photoshop CS) or ‘Image’ > ‘Adjustments’ > ‘Curves’. Don’t be worried this layer doesn’t look correctly exposed in the areas where the original does - just make sure that the brightness of the ground on the background layer looks about right when viewed together with the sky on the layer you are adjusting.

Here’s the layer duplicated, and the adjustments menu that contains the curves and shadow/highlight tool.

Here’s an example of using the Shadow/highlight tool to darken the highlights.

To see if you’ve got the balance about right, you can turn off the visibility of the top layer by clicking on the picture of an eye next to the layer. Don’t worry that the brightness doesn’t match exactly in the two areas you are working on— as long as you darken or brighten by at least as much as you will want in the end, you’ll have more control over matching in future steps.

To start simulating the ND filter, add a layer mask to the brightened (top) layer. Do this by holding Alt (or Apple) and clicking on the circle-inside a square on the layers palette. When you add the mask, your brightened layer will disappear.

Now, select the “gradient” tool by right-clicking (or option-clicking) on the paint bucket and selecting the gradient.

In the upper right of the screen, a small sample of the currently selected gradient will appear. Clicking on that gradient will make it possible to change the color and transparency of the gradient.

The goal is to create a gradient that is always opaque (controlled by the sliders on the top of the large gradient bar) and that goes from white to black (controlled by the sliders on the bottom of the large gradient bar).

Make sure that the layer mask is selected by clicking on the black rectangle next to the top layer. Now, apply the gradient. Assuming that the gradient goes from white to black, you’ll want to click where you want the (now masked) top layer to start transitioning in brightness to the background layer and drag the mouse to the point where you want the transition to be completed. The longer the line you draw with the gradient tool, the more gradual the transition will be between the new and old layers.

Now you can make sure that you like the match between the two layers by adjusting the opacity of the top layer in the layers palette. After some color adjustments, I ended up with a final image like this:

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