It used to be pretty easy, if you wanted to magnify a certain area in your Photoshop document you would grab the Zoom Tool, click and drag and POW that area would fill your screen. But one of the new improvements that Adobe came up with takes away this option, at least as a default option.
Now, if you click and drag, the point your on, not the area you mark, will grow. If you move rightwards and downwards, it will grow (zoom in). And if you move Leftwards and upwards in will shrink (zoom out). For those who have been with Photoshop for a while this is annoying, but the good news is that there is a way of turning this off:
1. Select the Zoom Tool and then look at the top horizontal options bar for the tool.
2. Locate the Scrubby-Zoom check-box, it should be checked. Un-check the box, and you’re ready to go. From now on when you click and drag, you’ll select and enlarge an area.