Learn how to create RGB and CMYK alpha channel files in Photoshop for professional image masking. This tutorial covers color mode conversion, transparency setup, and saving high-res TIFF and PNG files.
Video Transcript
In this video, I am going to demonstrate creating the RGB and the CMYK alpha channel files required by the designer to create an image mask.
I am using this frame.jpg file as a demonstration.
What we wish to do, in the end, is to make the center of the frame transparent to allow the images to be placed in there while giving a clean edge around being bordered by the frame.
To do so, let's begin with converting our RGB image into a CMYK mode by going under Image, Mode, CMYK Color.
The image is now in a CMYK color space.
Now we need to move the image to a layer that will support transparency.
We can do so by selecting the entire image, cutting it, creating a new layer, and then pasting it into the layer.
Now with the image in the new layer that supports transparency, we can delete the background layer.
Now we can switch over to our magic wand tool to select the inside area that we wish to convert to transparent.
We select it, we delete the inside, revealing the canvas background indicated by the checkerboard pattern.
With our selection still highlighted, we go to Select, Inverse, which now selects the inside of the frame all the way to the edge of the document.
We now click down here in our channels palette to create a new alpha channel.
Here we can see the new alpha channel has been created.
We can turn it on.
The red indicates the area of transparency.
Everything else will be opaque.
We can now deselect.
With these changes being made, we can now save this as our high-res CMYK image.
To do so, we go to File, Save As.
We change our format to TIFF.
We make sure we have alpha channels selected.
We name accordingly.
We click save.
We can use LZW image compression and save transparency.
Click OK.
We have now created our CMYK alpha channel TIFF.
Now to save the RGB version, we can go to File, Save for Web and Devices.
This will open up a mini-window.
Here we need to make sure it's set to PNG and transparency is selected.
We can click save and name accordingly.
We have now successfully created both our CMYK TIFF and our RGB PNG files that are required for the designer to use as an image mask.