Scaling and cropping images on the cheap
Reader Curtis Wagner has an inquiry about images. He writes:
For a Web site I’m working with I need to use images—both screenshots and photos—of very specific sizes. I’m on a budget so I can’t afford something like Photoshop to do this. Is there a cheap/free way?
Sure. For exactly no money you could attempt to create images of the correct size when you capture them or you could later crop and/or scale your images after you’ve captured them.
For screen captures, press Command-Shift-4. A target cursor appears. Click and drag over the area you want to capture. As you do, you’ll see a readout of the horizontal and vertical pixel area you’re capturing. When you let go of the mouse button, the capture is triggered.
Of course this technique is very little help to you if the object you’re attempting to capture is larger than the size you desire. In such cases you’ll want to capture what you want and then crop and/or scale your image. (In the case of photos and spot art, you’ll go directly to the crop and scale method.)
This can be done for free with the Preview application. Just open your image in Preview and choose Tools -> Adjust Size. In the resulting sheet you can select a specific width and height in pixels, percent, inches, centimeters, millimeters, or points. By default, images will scale proportionally they appear in the same aspect ratio as the original, but you can switch this option off if you’re not concerned about the images becoming distorted (when you want to lop off just a couple of pixels, for example).
If the original isn’t close to the aspect ratio you need, you should first crop it. You can do this within Preview as well. With the Rectangular Selection tool chosen from the Select menu at the top of the image’s window, drag over the area you want to select. You’ll see a pixel selection readout similar to the Command-Shift-4 screen capture tool. If you hold down the Option key while dragging, the selection will be centered on the point where you first clicked. Hold down the Shift key, and your selection will be a square.
Once you’ve made your selection, choose Tools -> Crop (or, faster yet, Command-K).
Of course there are any number of third-party tools that do this (and more). I use Xtralean Software’s $20 ImageWell because it allows me to resize images and convert them to other formats very quickly. If you use another free or inexpensive editor, please drop its name in the comments area below. I and other readers will appreciate it.