Selectively improve exposure
- — 09 January, 2007 10:15
Select just the sky
Instead of brightening the entire image, let's focus on the underexposed section. To do that, select the Freehand Selection tool from the third cubby on the toolbar on the left side of the screen, and then choose Smart Edge from the Selection Type menu in the Tool Options palette atop the screen. (If the Tool Options palette isn't on screen, choose View, Palettes, Tool Options.)
Now carefully select the sky by clicking along the mountain ridge a little at a time, then working your way around the sides and top of the photo. Double-click when you get back to your starting point. If you make a mistake, right-click to start the selection over. Don't bother trying to cut around the three trees on the left that jut into the sky; just keep following the contour of the mountain.
Once the entire sky is selected, choose Selections, Invert. This "flips" the selection so the sky is the only part of the scene that isn't selected. Clever, no?
Try the histogram again
Now you can reapply the histogram, using the same settings we tried at the beginning of the task. How does it look?
It's possible that you ended up with an ugly, overexposed seam along the ridgeline. That's because the selection includes the edge of the trees, which have little bits of sky mixed in. To fix this problem, undo the histogram adjustment and choose Selections, Modify, Contract. Set the tool to about 5 pixels and click OK (if necessary, you can use other selection tools to recapture the sides and bottom of the photo). Finally, run the histogram adjustment one more time.
This is what I got as my final result --notice that we got all the detail in the mountain, but the sky remains the same.