History+Palette+Undo

=Photoshop History Palette explained=

History Palette
The history palette can be opened by clicking on **WINDOW > History.** The history palette is located in the palette well. The history palette records the last 20 Photoshop actions. This is a really useful tool allowing you to restore you work to previous versions if you made a mistake. Photoshop History Palette The history palette also allows you to take a **SNAPSHOT**  of your workflow, this enables you to restore your workflow to that point. A snapshot of your workflow can be taken by clicking the camera icon at the bottom of the palette. Creating a history SNAPSHOT

This will save this point in your workflow, even if you have moved passed 20 actions. The snapshot will be stored at the top of the palette along with the original image. The **number of 'states' can be changed**. Should you wish to do this go to Edit > Preferences > General and change the number in the 'History States' box, click OK. Remeber we did this in preferences. We changed it to 50. Remember, the more 'History States' you set, the amount of memory assigned to this function will also increase. Also remember that 'History is volatile' - that is, it will be erased as soon as you close the file. Next time you open the image, the 'History' will be void and begin anew. As one progresses through the various states when working on an image, the states are 'recorded'. When the figure for the maximum number of states is exceeded, the 'state' at the top of the list disappears and is replaced by the one below it and so on. To preserve one of the 'states' in the list, click in the small square to the left of the required state in the History Palette and as the list creeps toward the top of the stack, the chosen 'sate' will remain fixed at the top. See below: || Taking a closer look at the History Palette, click on the fly-out arrow at the upper right corner. This reveals a menu which includes 'New Snapshot'. A 'Snapshot' is a moment in time that can be held as short-term memory in 'History'. Many 'Snapshots' can be taken and each one given a title if needed. ||
 * **The History Brush - 'Making History Work for You' ** ||
 * Most people use the 'History Palette' as a 'rescue device' - a way of returning to an earlier state during the evolution of a picture. Before exploring the 'History Brush', here's a brief 'History Primer'. ||
 * The History Palette's normal 'default' condition displays the last 20 functions ('states') performed.
 * The History Palette's normal 'default' condition displays the last 20 functions ('states') performed.
 * The History Palette's normal 'default' condition displays the last 20 functions ('states') performed.
 * [[image:http://www.crhfoto.co.uk/crh/history-brush/hist-palette-1.jpg align="absMiddle" caption="external image hist-palette-1.jpg"]] ||
 * It's possible to preserve more than one state by making 'Snapshots'.
 * It's possible to preserve more than one state by making 'Snapshots'.
 * It's possible to preserve more than one state by making 'Snapshots'.
 * [[image:http://www.crhfoto.co.uk/crh/history-brush/hist-snapshot.jpg align="absMiddle" caption="external image hist-snapshot.jpg"]] ||
 * To return to any given 'state' simply click on it. ||
 * <span style="font-family: arial,helvetica,sans-serif;">To return to any given 'state' simply click on it. ||
 * <span style="font-family: arial,helvetica,sans-serif;">To return to any given 'state' simply click on it. ||