Undo and history

By using the Undo/Redo commands and the History panel, you can easily control the state(s) of your images.

Beginning with the October 2018 release of Photoshop CC (20.0), you can undo multiple steps in your Photoshop document using Control + Z (Win) / Command + Z (Mac). This new multiple undo mode is enabled by default.

To perform undo or redo operation, do the following:

• Undo: Moves one step back in the undo chain. Choose Edit > Undo or use the keyboard shortcut Control + Z (Win) / Command + Z (Mac).
• Redo: Moves one step forward. Choose Edit > Redo or use the keyboard shortcut Shift + Control + Z (Win) / Shift + Command + Z (Mac).
  

The Edit menu also displays the name of the step that will be undone next to the Undo and Redo commands. For example, Edit > Undo Edit Type.

Revert to the last saved version

Restore part of an image to its previously saved version

Cancel an operation

Receive notification when an operation is completed

A progress bar indicates that an operation is being performed. You can interrupt the operation or have the program notify you when it has finished the operation.

Using the History panel

You can use the History panel to jump to any recent state of the image created during the current working session. Each time you apply a change to an image, the new state of that image is added to the panel.

For example, if you select, paint, and rotate part of an image, each of those states is listed separately in the panel. When you select one of the states, the image reverts to how it looked when that change was first applied. You can then work from that state.

You can also use the History panel to delete image states and, in Photoshop, to create a document from a state or snapshot.

To display the History panel, choose Window > History, or click the History panel tab.

Keep the following in mind when using the History panel:

• Program-wide changes, such as changes to panels, color settings, actions, and preferences, are not reflected in the History panel, because they are not changes to a particular image.

• By default, the History panel lists the previous 20 states. You can change the number of remembered states by setting a preference under Preferences > Performance. Older states are automatically deleted to free more memory for Photoshop. To keep a particular state throughout your work session, make a snapshot of the state (see Make a snapshot of an image).

• Once you close and reopen the document, all states and snapshots from the last working session are cleared from the panel.

• By default, a snapshot of the initial state of the document is displayed at the top of the panel.

• States are added to the bottom of the list. That is, the oldest state is at the top of the list, the most recent one at the bottom.

• Each state is listed with the name of the tool or command used to change the image.

• By default, when you select a state, the states below it are dimmed. This way you can easily see which changes will be discarded if you continue working from the selected state.

• By default, selecting a state and then changing the image eliminates all states that come after it.

• If you select a state and then change the image, eliminating the states that came after, you can use the Undo command to undo the last change and restore the eliminated states.

• By default, deleting a state deletes that state and those that came after it. If you choose the Allow Non-Linear History option, deleting a state deletes only that state.

Revert to a previous image state

Delete one or more image states

Create or replace a document with an image state

Set history options

You can specify the maximum number of items to include in the History panel and set other options to customize the panel.

Set Edit History Log options

You may need to keep careful track of what’s been done to a file in Photoshop, either for your own records, client records, or legal purposes. The Edit History Log helps you keep a textual history of changes made to an image. You can view the Edit History Log metadata using Adobe Bridge or the File Info dialog box.

You can choose to export the text to an external log file, or you can store the information in the metadata of edited files. Storing many editing operations as file metadata increases file size; such files may take longer than usual to open and save.

By default, history log data about each session is saved as metadata embedded in the image file. You can specify where the history log data is saved and the level of detail contained in the history log.

Make a snapshot of an image

The Snapshot command lets you make a temporary copy (or snapshot) of any state of the image. The new snapshot is added to the list of snapshots at the top of the History panel. Selecting a snapshot lets you work from that version of the image.

Snapshots are similar to the states listed in the History panel, but they offer additional advantages:

• You can name a snapshot to make it easy to identify.

• Snapshots can be stored for an entire work session.

• You can compare effects easily. For example, you can take a snapshot before and after applying a filter. Then select the first snapshot, and try the same filter with different settings. Switch between the snapshots to find the settings you like best.

• With snapshots, you can recover your work easily. When you experiment with a complex technique or apply an action, take a snapshot first. If you’re not satisfied with the results, you can select the snapshot to undo all the steps.

Create a snapshot

Work with snapshots

Paint with a state or snapshot of an image

The History Brush tool  lets you paint a copy of one image state or snapshot into the current image window. This tool makes a copy, or sample, of the image and then paints with it.

For example, you might make a snapshot of a change you made with a painting tool or filter (with the Full Document option selected when you create the snapshot). After undoing the change to the image, you could use the History Brush tool to apply the change selectively to areas of the image. Unless you select a merged snapshot, the History Brush tool paints from a layer in the selected state to the same layer in another state.

The History Brush tool copies from one state or snapshot to another, but only at the same location. In Photoshop, you can also paint with the Art History Brush tool to create special effects.