There are a few ways to do it:
1. you can use the cropping tool and enter values in the fields at the top for dimensions and resolution and then the crop tool will crop to that size.
2. you can go to the image menu and alter it in the image size part.
3. you can do a 'save for web' and alter it there.
4. (not recommended) but you can alter the canvas size and then use the transform tools to scale your selection.
Be aware that if you are using a more recent version of Photoshop (CS2 onwards) and you use the last suggestion, it's a wise precation to make your image a 'smart object' as when you scale a smart object, it retains the data of its original size.
|