Alpha channels are invaluable tools at times; there is nothing that can replicate their power. So knowing how to create them is something that is very important.
A coworker and I found an interesting “nuance” to creating them today. Typically, I’ll make a selection of the layer I want the alpha channel of, add other layers that I want to use as well, and then save the selection as a new channel and I’ve got my alpha. It’s worked for me multiple times in the past.
But today we couldn’t get the correct levels of opacity for certain layers in CS3 (and replicated in CS2). Upon further investigation, the alpha channel wasn’t rendering out correctly for adjusted layer opacity or blending modes.
After some playing around, we did find a solution to this though. However, this will only work in CS3 and beyond. Take the layers you want to create the alpha channel out of and make them into a smart group. You can then use the smart group to create your selection and save the alpha channel.
