I may not be fully understanding your reply. I do realize that from the contact sheet, I can change the cursor to a zoom icon and zoom exactly where I would like to view details, but is there a way to do this from the "Preview" screen as this is how I typically do my editing. My preference is to leave a strip on the bottom with thumbnails and have the selected image filling most of the screen. I can then toggle back and forth between images in this view and often zoom in to look at details. It is on this screen that I was wishing I had a controlled zoom feature where I could zoom in to the part of the image I am interested in seeing at 100%. Is this already a feature that I am not aware of, I apologize. If this is not possible, this is the feature that I was requesting.