Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
I honestly believe that one of the most important features in Photoshop is the ability to undo whatever you just did. Because just knowing that nothing that you do in Photoshop is permanent, allows you to experiment and really play with your images. For example, if I go to Image > Image Rotation > Flip This Canvas Horizontally, it's really easy to simply Undo that last command. I can choose Edit > Undo Flip Canvas Horizontally or we could use the keyboard shortcut Cmd+Z on the Mac or Ctrl+Z on Windows.
Now as we work along and we do more and more things to our image, Photoshop is actually keeping track of all of the things we do in a History panel. If you're in the essentials workspace, you'll notice that your History panel is set to iconic mode. If we click on that it will go ahead display it for us. If we are in a different work space or your History panel isn't showing, you can select Window > History. My History panel is rather large and that's because I've used the grabber icon at the bottom in order to drag it down. This way as I build up history we'll be able to see those states. To quickly build up history in this image I'm just going to use the paint brush tool and paint in the image.
So I tap the B key and that gave me my paintbrush. It's going to paint with black because that's my foreground color and, as I drag a stroke across the sky, we can see that that gesture has now been recorded in my History panel. If I want to step backwards in time, I can simply click on the Open state. Or I can move forward to the Brush tool. Let's go ahead and make a few more strokes with a Paintbrush tool, and we can watch the history build in the history panel. But now if I decide to go back in time, and I skip back to when I first laid down the first brushstroke, you can see that the rest of the history states are grayed out.
If I make another brush stroke right now, these history states will actually disappear. In fact, we can do that. I'll make a second brush stroke. And we can see that I've lost all of those other states to go back to. I can still go back to the original state and toggle to this state, but they're the only two that I have left. If you want Photoshop to keep track of nonlinear history. Meaning that if you want to make a bunch of paint strokes, and then be able to go back in time, but still have all of these available.
Then you'll want to use the flyout menu on the history panel, and choose history options. The option that you want to check is the allow nonlinear history. As soon as I select that, and click OK, you'll notice that these states are no longer grayed out. And if I start creating another paint stroke here, they don't disappear. Instead, this paint stroke just got added at the bottom of my history. So I can still move back through all of those different states. If I want to use a keyboard shortcut to move back and forward, through the different history states, I can use the step backward and step forward keyboard shortcuts.
So in this case, if I want to step backwards, I'll use Command+Option+Z. If I want to step forward, I'll use Command+Shift+Z. Course the Ctrl key is the Cmd key on Windows. If I make enough paint strokes, you'll notice that the top most state here, the open state, eventually will roll off the top. Because by default Photoshop is not going to keep track of an infinite number of states. In fact, it just rolled off the top because I must have hit 20 different states.
If you want to increase the number of states that Photoshop keeps track of, then on the Mac, you'd choose the Photoshop menu. On Windows, you'd choose Edit > Preferences > Performance. It's right here that you would tell Photoshop how many History States that you'd want to keep track of. Now, it might be your first instinct to think that you want to put this as high as possible. But don't forget every time you make a change to your image, if Photoshop has to keep track of that state and the state before and before, if it's gotta keep track of 100 of those states, those states have to be kept somewhere in memory.
And if you're working on large files, eventually you'll run out of RAM. And Photoshop will have to write all of its temporary files to the hard drive so you might notice a performance hit. Now, Photoshop is smart enough. It doesn't have to write the entire file every time you make a change. It's breaking up the document into little sections or tiles and it's only remembering the changes that you made to that section. Of course, if you run a filter over your entire image, then it will have to keep track of all of that information but what we were doing just making the small brush strokes it only has to keep track of a little bit of information.
So you just need to decide a good balancing point. I think that the default history state set to 20 should be a good amount. So I'll just click OK. Now, if you get so far along in your image where you can't get back to the point that you want to. You have really three different options. We could close the file without saving it. We could go to File > Revert or you can click on the Snapshot at the top of the History panel. And this snapshot was created because of an option that's on by default under history options.
Its this option right here the automatically create first snap shot. And I like to leave that on because there's actually an advantage to have that snapshot. And that is when you choose to close the file without saving, or when you choose revert, both of those instances cause Photoshop to reread your file from the hard drive. If you simply click on this first snapshot, if that snapshot is sitting in RAM Then Photoshop can just grab it out of RAM which is much faster than reading that file on your hard drive. All right, so I'll leave that turned on, but I am going to turn off the Allow Non-Linear History for now and click OK.
And then we'll click on that initial snapshot. So you can see that the ability to go back in time using multiple undo and the history panel is a huge advantage as it enables you to work in a much more flexible environment. Where you shouldn't hesitate to try something new.
Get unlimited access to all courses for just $25/month.Become a member
180 Video lessons · 75852 Viewers
64 Video lessons · 94434 Viewers
86 Video lessons · 61947 Viewers
103 Video lessons · 31270 Viewers
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.