Using drop shadows in Photoshop not only adds depth to any layers in your work, it's particularly useful with text. Text tends to be more noticeable and more legible when a drop shadow is added, especially when the font is a similar color to the background. Photoshop CC 2014 has several different settings for drop shadows. Knowing what each setting does and which ones should be changed, will make it easier to create the effect you desire in each project.
Drop Shadows in Photoshop
Drop shadows are a type of layer style, so you must first select a layer in the Layers panel that you want the drop shadow applied to. To add a drop shadow, click the "Layer Style" button at the bottom of the Layers panel, or select "Layer Style" from the "Layers" menu above the canvas. Select "Drop Shadow" from the drop-down menu. This opens the Layer Style window with the drop shadow option already applied. For best results, the layer below should be a relatively light color. Adding a drop shadow to a background layer won't give you any effect, since there's nowhere for the shadow to fall.
Drop Shadow's Default Settings
When the Layer Style window opens, it creates a thin, semi-transparent shadow located on the bottom-right of the object. Like a real shadow, the drop shadow takes on the contours of the object. If it's a text layer, the shadow follows the contours of each letter. Changing the settings in the Layer Style window will adjust the shadow's appearance. You should note, however, that the Blend Mode and Quality Settings are already optimized for nearly any shadow you might want to create. Changing them usually won't give you satisfactory results. To go back to Photoshop's defaults, just click the "Reset to Default" button.
Drop Shadow's Light Angle
The Angle setting controls the direction of the simulated light that creates the drop shadow. Consequently, moving the "Angle" directional dial so it points straight up, makes the shadow appear directly below your object. Since people are used to light coming from above, for most objects, including text, try moving the angle anywhere between 130 and 50 degrees. You might note that the Angle text field isn't quite like a compass. Ninety degrees is straight up, minus 90 degrees is straight down and zero degrees is a light source on the right.
Drop Shadow Settings
Experiment with the drop shadow settings to manipulate how the shadow appears. To make the drop shadow darker, increase its opacity setting. A high opacity is good for creating contrast. If there are fine details you want to be visible below the shadow, try decreasing the opacity to make the shadow more transparent. Changing the distance setting moves the shadow farther from or closer to the object. For text, Adobe recommends a distance setting between 4 and 10 pixels. Increasing the spread setting makes the shadow thicker. This can be an effective setting for text, but it seldom makes much difference with large objects. Increasing the size setting makes the shadow larger but also more blurry.