When your photo seems lackluster and you want to give it a little punch, try making a Levels Adjustment to improve the brightness and contrast. A quick fix, this is the first step I take when I sit down to edit my photos.
Open a photo in Photoshop or Elements.
Create a Levels Adjustment Layer by clicking the “Create a New Fill or Adjustment Layer” icon at the bottom of the Layers Panel. This looks like a circle that is half-black and half-white (or a black-and-white cookie!) Choose “Levels.”
Note: In older versions of Elements without the Adjustment Layers icon, make a copy of your photo first by pressing Ctrl J (Mac: Cmd J.) Press Ctrl L (Mac: Cmd L) or select Enhance > Adjust Lighting > Levels from the Menu bar. This will allow you to adjust levels, but does not create an Adjustment layer.
The Levels Adjustment function adds a layer to your Layers panel right above your photo and it also opens the Adjustments panel. Find the histogram in the center of the Adjustments panel. Ideally, this should look like a mountain, but often does not. The information may be bunched up closer to the white end (right) or the dark end (left.)
In the full version of Photoshop check the Preview box (if it is not already checked) and make sure RGB is selected.
Under the graph, drag the black and white triangle Input Levels sliders inward (to or beyond the first pixels shown in the graph) to increase the contrast. Watch your photo highlights and shadows change as you drag the triangles. Be careful not to “blow out” the highlights (lose details in the white areas) by dragging the white input too far. Now drag the Midtone slider left or right to fine-tune to lighten or darken the photo midtones in your adjustment.
If your original photo is too contrasty to begin with, use the Output points instead. These are found on the bar under the histogram. Drag them toward the middle to adjust the maximum white or black to shades of gray, changing the tonal range.