news • 24 January 2024

How to Generate an Alpha in Photoshop

In this article, 2D VFX Tutor Lorenzo Maniccia covers matte paintings, alpha channels and how they work together, demonstrating an easy and quick way to generate an Alpha in Photoshop. 

Matte paintings are essentially digitally rendered backgrounds used to seamlessly extend real-world environments or create entirely new ones. In Photoshop, creating a matte painting involves layering and manipulating various elements like textures, landscapes, and architectural details. 

Alpha channels control the transparency of individual pixels within an image. You can use an alpha channel to create a mask, revealing or hiding parts of the image layered on top. For matte paintings, this allows you to seamlessly blend the painted elements with the foreground objects, creating a realistic illusion of depth and extension. 

Nuke is a powerful compositing software used in the film and visual effects industry. Projections in Nuke allow you to quickly match-move a new element without necessarily involving other departments. 

In the video tutorial below, Lorenzo shows how to generate an Alpha in photoshop. The Alpha image can then be exported into Nuke and copied into an RGB exr with a Copy node. This process is quite handy if you are working on projections and matte painting.