There are many techniques of creating shadows in Photoshop but today I will show you how to create realistic 3D shadows using Photoshop’s 3D features. You will learn how to cast realistic shadows of your models or objects.
Casting a realistic 3D shadow in Photoshop
The first thing you need to do is have your model/object on a separate layer and with transparent background.
Create a copy of it and make sure there is no layer mask on it. If you have a layer mask, apply it. The secret to a realistic shadow with this technique is turning your model/object into a 3D extrusion.
Right click on the model’s layer and choose “New 3D extrusion from selected layer“. This will create a physical 3D extrusion of your shape (model or object) which can be illuminated and cast a real shadow on your background.
Creating the Extrusion will take you to the 3D workspace. The extrusion depth should not be very high. In this case just 3-5px is enough.
Select the Infinite light and rotate it around to place the shadow however you want on your plane and increase its Intensity to also increase the intensity of the shadow. You can also soften the shadow if you want using the Softness slider.
Use the Environment settings to set your shadow’s Opacity and Color and then render or rasterize your shadow. Watch the video to see more details and learn how to render the shadow only and not the extrusion.