Photoshop/101basics/The Basics/Workspace/menubar/layer/layers effects/innershadow

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=> Photoshop Layers Basics ==> Layers Style Effects ==> Inner Shadow Style

Inner Shadow Style

Blend Mode: To know about the Blending modes please go to it's own page.

Color : This will define the shadows color

Opacity: This will determine the color's density of the shadow.

Angle: This will determine the angel in which the shadow would appear, you can either enter an angle or move the hand on the angle circle.

Distance: This will determine the distance between the object and it's shadow.

Spread: This will determine how much the shadow would spread.

Size: This determines the size of the shadow.

Contour: There are different layouts for the shadows, you can choose one of them, of how the light should distribute. Allowing you to create transparent palaces within the effect.

Noise: This determiners if the shadow is noised (distributed in little dots)

Preview: This box shows a sample of how the shadow is being applied.

A sample of how the Drop shadow Works:

Without an effect & With an inner shadow effect