Lightroom can automatically stack similar photos together based on how much time passed between poses, or a lighting change, or a location change. This principle works on the premise that while you’re shooting, you’re shooting fairly continuously. However, when you change poses, lighting, location, and so on, there’s a short (or long) pause while you set up the next shot. You tell Lightroom how long you think your average pause is, and everything with a shorter pause gets stacked. (This trick works better than it sounds.) To turn on this auto-stack feature, Control-click (PC: right-click) any thumbnail. From the contextual menu, choose Stacking > Auto-Stack by Capture Time. The dialog box shown in Figure 10 appears. As you drag the slider left or right, photos will start jumping into stacks in real time. This is one of those features you just have to try to see that it usually works pretty darn well.