I've been using Photoshop only for around 175 years, so you can hardly blame me for the following stupid question. When I zoom in or out of a particular image, I zoom in or out on all the windows I have open, and God knows I don't want to! I want the non-active windows to remain blissfully ignorant of what I'm doing in the open one! Does anyone know how to make this happen?
Select your Zoom tool and check the control bar along the top of the screen. There should be a small checkbox labeled "Zoom All Windows." Deselect that and you should go back to zooming the active window while the rest keep minding their own business. Zooming with the keyboard (command/control-plus and -minus) seems to ignore the setting as well.