Adobe has tweaked Photoshop’s Brush and Zoom tools to great effect. While you can still change brush size with the [ and ] keys, you can now interactively change brush size by holding down Control and the right mouse button under Windows (Control and Command on a Mac). With these modifiers held down, you simply drag the mouse to re-size the cursor. Photoshop shows the cursor in red, including blurred edges to represent feathering. By holding down the Alt or Option key in addition to the other modifiers, you can change the hardness of the edge by dragging.
Once you learn the modifiers, you’ll quickly adapt to resizing your brush while painting. It\'s a much easier method than using the keyboard.
With CS4, Adobe finally decided to leverage the power of the graphics processing units in almost all modern computers. In previous versions, when you clicked with the Zoom tool, Photoshop re-drew the image at the next pre-set magnification level. While the Zoom tool still works this way, you can also simply hold down the mouse button to see a smooth zoom in, with an accompanying pan to center the image around the Zoom tool.
In addition to looking really cool, this behavior makes precise zoom amounts much easier. At around 500% magnification, Photoshop begins superimposing a pixel grid over your image. This can facilitate individual pixel edits, but if you don\'t like it, you can deactivate the grid.
The improved zooming is also more accurate. You’ll no longer see jagged edges on high-contrast lines when zoomed to odd percentages.
If you zoom into a particular magnification, then hold down the H key and click with the Zoom tool, Photoshop zooms out to fit to window, and a small rectangle appears next to your cursor. This indicates the crop of your last zoom. Position the rectangle somewhere else on your image, click the mouse, and Photoshop automatically zooms that area in to the same magnification. While it\'s an interesting addition, I don\'t use it much in real-world work. However, different users work in different ways, so some of you might find it more compelling.
If you release the mouse button while quickly panning over a document, the image zips across the canvas, then slowly coasts to a stop. It\'s a little more effective with a stylus and tablet than with a mouse, though not necessarily any easier than using scroll bars.
If you use a tablet, you’ll love the new Rotate View menu, which lets you rotate the view of your image within the document window. It\'s not a rotation of the image on the canvas, but simply a virtual equivalent of rotating your computer monitor. I’s like rotating your drawing surface so you can more easily draw along a particular axis, rather than drawing at 90° angles relative to the sides of the tablet. Double-clicking on the Rotate View tool returns the image to its normal orientation.
Corel Painter has had this feature for years, and I\'m happy to see it in Photoshop. Rotate View is the only feature besides Zooming that\'s GPU-accelerated. It’s great to see Adobe taking advantage of this extra processing power; it bodes well for future innovation and acceleration. Your graphics card must be OpenGL-compatible, but most GPUs are these days.