How (and Why) to Zoom on the Mac

| How-To

My goal for this article is to expose you to a particularly useful utility in OS X's Accessibility feature–Zoom. I have taught all things-Mac to many, many people over the years, and I often find that this one feature is remarkably overlooked. When I show them how to enable Zoom, the gasps are deafening, and delightful.

It’s likely that most Mac owners never venture into the wondrous mysteries of Apple’s stellar Accessibility features. Consider this: you DO NOT need to have a disability in order to derive the benefits that most Accessibility features happily provide. You should consider exploring this area. You will undoubtedly be surprised at what you find.

The Accessibility Preferences icon.

Accessibility is configurable via Accessibility Preferences in Mountain Lion.

Talking about Zoom might be somewhat humdrum, but it’s worth discussing because it provides an enormously valuable function for at least two very important reasons. One is better screen readability for failing eyesight, which comes with age (that would be my eyesight); another is using Zoom as a presentation aide when speaking to an audience–in particular, when demonstrating something on-screen.

Unfortunately, as with many other useful OS X capabilities, Zoom is disabled by default. You have to dive deep into System Preferences to locate its on/off switch. I will show you the way.

The Accessibility Preference panel with default settings.

The new Accessibility Preferences pane with default settings.

On Macs running OS X 10.8 Mountain Lion, you get to the Zoom controls via System Preferences > Accessibility.

It’s important to note that on earlier system versions – 10.7 Lion and older – most of these functions are found in the Universal Access Preference panel. However, others are found elsewhere.

Starting with Mountain Lion, configuring Accessibility is much easier and more intuitive. You will notice a complete interface makeover along with the name change, as well as consolidation of all Accessibility features. If you’re on an older system, the options will look and be positioned differently, but you have basically the same accessibility features available to you, including Zoom.

With the Accessibility Preferences open, click on the Zoom feature listed under the “Seeing” section in the left-hand column, as shown in the image below.  (In the older Universal Access Preference panel, you unfortunately need to visit the Keyboard Preferences panel for some of the Zoom features discussed here.)

There are many options and several sub-panels within the Zoom Preferences, and it will take very little effort to get things just right. Let’s look at the five principal controls you have for governing Zoom.

First, you are given two ways to activate Zoom. You can engage it, along with its variants, by using keyboard shortcuts. The controls for this can be seen at the top of the Zoom Preferences panel. Alternatively, you can Zoom by using scroll gestures on the trackpad or via the scroll wheel on a mouse.

For me, the scroll gestures choice is best, so I first enable Use scroll gestures with modifier keys to zoom. I choose the Control key in combination with the scroll gesture in order to achieve the desired Zoom level. You may choose any of the three modifier keys that work for you.

Detail from the Accessibility Preference panel.

Select which modifier key to press while using the scroll gesture to zoom in and out.

Once enabled and configured, you zoom in and out by pressing the selected modifier key while scrolling up and down on your keypad or mouse’s scroll wheel.

The next item, enabled by default, is “Smooth images.” This ensures that the zoomed images appear less know, smoother. Designers will recognize this setting as meaning “anti-aliasing.” For normal use, leave this enabled.

Next, we see  Zoom follows the keyboard focus. Let’s learn more about this by consulting the Help page. What was that? What do you mean, “What help page?” See that tiny circled question mark on the bottom-right corner of the Accessibility Preferences panel as shown in the first screenshot above?

Unfortunately, it’s ubiquity is only superseded by its lack of use. Simply click on it to get to the built-in system help pages. Anyway, we are told that this Zoom setting magnifies the area that has the “Keyboard Focus.” What the heck does THAT mean?

Keyboard Focus – it’s another obscure function, but highly useful for those with certain fine motor disabilities or folks who would rather use only the keyboard rather than a trackpad or mouse to navigate and engage controls.

This is linked to a setting in the Keyboard Preferences panel whereby, if enabled, it allows you to use the Tab key to cycle sequentially through the various windows, controls, and menu items. With this Zoom option enabled, the magnified area will center on where the current keyboard focus is, staying zoomed in while shifting to the next one when Tab is pressed. I have never observed anyone using this feature, and I don’t use it. But, it’s there for those who need or prefer to use it.

Finally, there is what’s known as the Zoom Style, and you have two to choose from in a pop-up menu. I’ve already mentioned that the Zoom function is helpful when presenting to an audience. This advantage is addressed by this setting.  By default, when engaging the Zoom function, you are doing so in Fullscreen Style. This shows the magnified image on the entire screen, and it’s how I normally do my zooming.

Detail from the Accessibility Preference panel.

Choosing one of two available Zoom Styles.

The other Zoom Style choice is Picture-in-picture. In contrast with the Fullscreen style, this one shows the magnified image in a small window that you can move around the screen as needed. It’s like holding a magnifying glass up to the screen, thereby helping you or your audience focus their attention and clearly see details as needed.

The Picture-in-picture frame can be pre-configured to any size you want. This is done by first making sure that the Picture-in-picture Zoom Style is selected in the Zoom Style pop-up menu, then clicking the More Options button. In the resulting pane, click on the Adjust Size and Location button at the bottom, as shown below.

Settings for adjusting the size of the Picture-in-picture frame.

Click Adjust Size and Location to modify the Picture-in-picture frame.

This brings up the actual Picture-in-picture frame, but in its editable mode, allowing you to size it as desired. It’s just like resizing any Mac window by hovering the pointer over the window’s edge. When the pointer changes to an arrow, you can drag and position the window edges as needed. Then click OK to exit.

I will occasionally switch to the Picture-in-picture Zoom Style when running a demo on the Mac projected to a group of students. It’s perfect for when I need to focus on a small detail that would otherwise be impossible to see in a large classroom setting, like a menu command or a button. Note that there are third-party apps that provide this type of functionality. But you know me–I like to show you what’s free and already built into OS X.

Let’s revisit that More Options button at the bottom of the Accessibility/Zoom Preferences Panel. The resulting panel varies depending on the Zoom Style selected. Furthermore, you are able to set a number of very specific options for each of the two Zoom Styles. Some of the resulting changes are very subtle. Most are intended to benefit users with disabilities by giving them the capability to fine-tune how the overall OS X Zoom function works.

In any case, I strongly suggest you experiment with all these settings to see what works for you for however you need or want to use the feature.

In summary, here’s how I configure Zoom on my MacBook Pro:

Keyboard Shortcuts: I keep this option disabled. I’m not big on keyboard shortcuts. But that’s just me. Some people swear by them.

Use scroll gesture with modifier keys to zoom: This is my preferred method for engaging the Zoom. My modifier key of choice is the Control key which I keep pressed while performing the default two-finger scroll-up/down swipe on the keypad. And so, when I come across some molecule-sized or otherwise difficult-to-read text, I engage the Zoom with a quick swipe up then back down, along with the Control key.

Smooth Images: This stays enabled. I don’t care to see pixelated details on screen.

Zoom follows the keyboard focus: I don’t use keyboard focus, so this stays disabled.

Zoom Style: My permanent choice is the Fullscreen Zoom Style. It’s perfect for everyday use. I don’t know if it’s just me, but nowadays so many websites use tiny light-gray text on light backgrounds. It’s vexing, and I wish they’d stop doing this! Nevertheless, being able to zoom in-and-out quickly really, really helps.

Example of using Picture-in-picture Zoom style.

The Picture-in-picture Zoom style comes in handy when demonstrating software.

The Picture-in-picture Zoom Style has it’s uses as well. When needed, while presenting or doing a software demo, I temporarily switch to this style to ensure that the members of my audience clearly see what I need them to focus on.

No matter what you see on your screen, no matter which application you are running, the OS X Zoom function is a big help – not only to those with disabilities, but to any Mac user who wants to better see screen detail.

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Thanks for this article. 

I have been using zoom for a while (old eyes, large screen, small text), and find it very useful.  One thing you pointed out that I was not aware of is the “picture-in-picture” style.  I think that might be quire useful in creating screen captures for training guides.  Something I do a lot of.

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