I am working with a third party model and need to change the specular map. The model material is using the spec map's alpha channel information. I have opened the spec map in Photoshop and if I go to the Channels tab I can see the Alpha 1 channel with the alpha information that I need to change.
What I would like to do is make a copy of this original and drag it into the Layers tab, so that I can revert back to this if need be. I can then duplicate this again and paint over it to create the new alpha map. Once done I can then copy and paste it as the new alpha channel, keeping the original preserved in the Layers tab.
The problem is how do I get the Alpha 1 channel into the Layers tab to make the edits? I cannot click and drag it there; and if I do Select All, Copy and Paste into a new layer nothing is pasted. How can this be done?
If I'm not using the best workflow for editing an existing specular map please suggest an alternative way. I basically just want to edit the alpha channel but keep the original as well.