Adobe Photoshop CS4 - Manual (Page 55)

48 USING PHOTOSHOP CS4
Workspace
Last updated 1/10/2010
Delete one or more image states
❖ Do one of the following:
• Click the name of the state, and choose Delete from the History panel menu to delete that change and those that
came after it.
• Drag the state to the Delete icon to delete that change and those that came after it.
• Choose Clear History from the panel menu to delete the list of states from the History panel, without changing the
image. This option doesn’t reduce the amount of memory used by Photoshop.
• Hold down Alt (Windows) or Option (Mac OS), and choose Clear History from the panel menu to purge the list
of states without changing the image. If you get a message that Photoshop is low on memory, purging states is
useful, because the command deletes the states from the Undo buffer and frees up memory. You can’t undo the
Clear History command.
• Choose Edit > Purge > Histories to purge the list of states for all open documents. You can’t undo this action.
Create or replace a document with an image state
❖ Do one of the following:
• Drag a state or snapshot onto the Create a New Document From Current State button in the History panel.
The history list for the newly created document contains only the Duplicate State entry.
• Select a state or snapshot, and click the Create a New Document From Current State button . The history list
for the newly created document contains only the Duplicate State entry.
• Select a state or snapshot, and choose New Document from the History panel menu. The history list for the newly
created document contains only the Duplicate State entry.
• Drag a state onto an existing document.
To save one or more snapshots or image states for use in a later editing session, create a new file for each state you
save, and save each in a separate file. When you reopen your original file, plan to open the other saved files also. You
can drag each file’s initial snapshot to the original image to access the snapshots again from the original image’s History
panel.
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.
1 Choose History Options from the History panel menu.
2 Select an option:
Automatically Create First Snapshot Automatically creates a snapshot of the initial state of the image when the
document is opened.
Automatically Create New Snapshot When Saving Generates a snapshot every time you save.
Allow Non-Linear History Makes changes to a selected state without deleting the states that come after. Normally,
when you select a state and change the image, all states that come after the selected one are deleted. In this way, the
History panel can display a list of the editing steps in the order that they were made. By recording states in a nonlinear
way, you can select a state, make a change to the image, and delete just that state. The change is appended at the end
of the list.
Show New Snapshot Dialog By Default Forces Photoshop to prompt you for snapshot names even when you use the
buttons on the panel.