With Photoshop's layering feature, you can composite separate images together for a number of purposes. For example, you can add your company's logo as a watermark on top of a product photo, or you ...
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Layer Masks in Photoshop explained

Masking is the secret weapon behind many jaw-dropping designs, making it one of the most powerful techniques you can master ...
Rasterizing a Photoshop layer converts a vector layer to pixels. Vector layers create graphics using lines and curves so they maintain their clarity when you enlarge them, but this format leaves them ...