...and you don't need layer masks. I don't know why I didn't think of it sooner! After you've taken several pictures with your camera on a tripod, open one and use the lasso tool feathered about 10 pixels and make a loose selection around the subject you want to place on another picture. Edit/Copy. Open up the other picture and paste what you lassoed. It will probably be placed in the middle of the screen. Just use your move tool to drag it where it belongs taking care to match up other elements of the picture. Just do this with each picture. When you're all finished and satisfied flatten the image and do your final editing (e.g. exposure adjustment, sharpening). This was taken before daylight arrived using flash bounced off a cathedral ceiling. Not wonderful lighting. Ricky is extremely difficult to light. His black fur absorbs the light. If I light him properly the rest of the picture will be overexposed (in this situation).