Adding Drop Shadows to Your Real Estate Photography in Photoshop | YouTube
Realism, depth, and perspective are just some of the words that will probably describe how an image in real estate photography can exude more impact. A photo that presents itself as a 3-dimensional image compared to a flat 2D render would more likely gain a better following as a result of appealing to aesthetic perceptions. Drop shadows is a perfect way to put that perspective in place. This technique that is available in most real estate photo editing software enables objects and elements to pop out, creating a distinction between two different planes of sight.
Reference: Photo and Video Edits | Adding Drop Shadows to Your Real Estate Photography in Photoshop