Zoom Palette
From ZBrush Info
The Zoom palette, docked in the left tray and with the mouse cursor over the Rgb button that appears in the area above the canvas. The two thumbnail views both show the area around the mouse cursor, in this case at differing levels of magnification.
Note: The Zoom palette is often docked into one of the trays, so the magnified thumbnail views are visible as the mouse is moved across the ZBrush interface and canvas. To do this, open Zoom palette from the menu bar, and click the small circular icon in the upper right corner of the palette.
Controls
Note: Many of the controls below have convenient keyboard shortcuts. Hover the mouse over the control and hold down the Ctrl key for a description of the control, including keyboard shortcuts.
Small and Large thumbnails: The small thumbnail (in the top left corner of the Zoom palette main area) and the large thumbnail (at the bottom of the Zoom palette) display a magnified view of the area around the mouse cursor. They can each display at magnifications of 2x, 4x, or 8x. Click on them to cycle through the magnification levels.
Scroll: Click and drag on this button to scroll the canvas within the drawing area. You can use this to get to areas of the canvas that are not visible in the drawing area.
Zoom: Click and drag up or down on this button to zoom the canvas in or out interactively.
Actual: Returns the canvas to its actual size.
AA Half: This sets the zoom factor for the canvas to exactly 0.5—50%. ZBrush treats this scale factor in a special manner; when the zoom factor is exactly 50%, the canvas contents are antialiased, which reduces the "jagged" effect that can appear along edges in a computer-generated image.
A common method of working with ZBrush is to create and draw your document at double its intended size, and then to use this button to display the antialiased version at the "final" size. The Document:Export button can then be used to export the smaller, antialiased version of your work.
On the left, a cube was drawn and saved at a normal (1x) zoom level. On the right, the same cube was drawn twice as large, the Zoom:AA Half button was pressed, and the resulting image was then saved. You can see the much smoother edges using the AA Half mode.
In: Click to zoom in on the canvas; this makes the canvas appear larger within the drawing area. Each click zooms in one level.
Out: Click to zoom out from the canvas; this makes the canvas appear smaller in the drawing area. Each click zooms out one level.
Zoom: Click and drag to increase or decrease zoom factor, or click once and enter a number with the keyboard. A value of 1 corresponds to a zoom factor of 100%, i.e. no zoom. Range = 0.1 to 32. Default = 1.
