From the course: Photoshop Masking and Compositing: Fundamentals

Unlock the full course today

Join today to access over 22,400 courses taught by industry experts or purchase this course individually.

Mixing a custom "fourth" channel

Mixing a custom "fourth" channel - Photoshop Tutorial

From the course: Photoshop Masking and Compositing: Fundamentals

Start my 1-month free trial

Mixing a custom "fourth" channel

I've gone ahead and saved out those last two versions of the image. So we now have Grayscale bird.psd and Single-channel grayscale.jpg. Now the reason I went with the native PSD format for the grayscale image is because I needed to retain those layers as well as that mask. So the great thing about native PSD is it allows you to save just about everything you can do inside Photoshop and I say just about, because there is no saving history. However, with the Single-channel grayscale image, I have just one Channel, there are no masks and I have a single Background. So I might as well invoke the JPEG compression, because that ends up delivering a smaller file for you. And speaking of file size it's important to note that just as with layers channels take up space on disk. So bare in mind each channel is another grayscale variation on the image. If you start with three channels in the case of an RGB image and go down one Grayscale channel, why then the new file is going to take-up at most…

Contents