Today’s Question: How do I toggle between a before and after rendition of a photo to which I have applied adjustments in Lightroom Classic?
Tim’s Quick Answer: You can quickly toggle between a “before” and “after” view in the Develop module in Lightroom Classic by pressing the backslash key (\). In addition, there are several other options for comparing an image with versus without the adjustments applied to it.
More Detail: Unfortunately, you do need to be in the Develop module in Lightroom Classic in order to switch between “before” and “after” views. However, there are a variety of ways you can evaluate the adjustments applied to an image when you are viewing that image in the Develop module.
As noted above, you can toggle between a full “before” versus “after” view of the image by pressing the backslash key (\) on the keyboard. In addition, there are several other view options for evaluating adjustments.
First, you can choose among a variety of views that enable you to directly compare the “before” versus “after” version of the current image. Below the image in the Develop module you can find a toolbar (if that toolbar isn’t visible, press the “T” key on the keyboard to toggle the visibility of the toolbar). Toward the left side of the toolbar you’ll find a button with the letter “Y” (possibly twice) on it. Clicking that button will cycle the view through several comparison options.
You can also click the popup just to the right of the button to see a menu where you can select among the view options. There are a total of four views, all of which involve a “Before/After” comparison. You can either view the before and after views side by side or above and below each other. In addition, you can choose to view the full “before” and “after” view, so you are seeing the full image twice, or you can choose a split view option. With the split view option you’ll see half of the image as the “before” version, and half as the “after” version, split left-to-right or top-to-bottom depending on the option you choose.
It is worth noting that you can also toggle the visibility for individual adjustment sections in the Develop module. To the left of the heading for each section on the right panel in the Develop module (other than the Basic section) you’ll find a toggle button that looks something like a light switch. You can click that button to turn off (or on) the full section of adjustments. So, for example, you can view the image with the Tone Curve section applied or without, just by toggling that switch.