Next is the numeric indicator of the zoom level, the zoom out button, zoom slider, and zoom in button. You can manually adjust the zoom level using the slider, or use the buttons to zoom in and out in regular increments.
To the far right is a small chain icon. This button is only available when in photo compare mode, and it locks the zoom level for both of the displayed photos so that when you zoom on one, the zoom level is maintained in the other. It also locks the orientation as you pan the photo around on screen.
Anytime the displayed photo is zoomed to a level that is larger than your screen, your cursor changes to a hand icon as you move it over the photo and you can click and drag to move the photo around.
