Use your Apple Mouse to zoom in on an image
If you use an Apple mouse, you can use it to zoom in on part of your screen.
Some portable computers also support making the screen image larger using the trackpad.
Choose Apple menu > System Preferences, click Accessibility, then click Zoom.
Select “Use scroll gesture with modifier keys to zoom” to turn on zooming, then choose a modifier key, or enter multiple modifier keys, to zoom with your mouse. (To use multiple modifier keys, press them at the same time.)
If you’re using an Apple Magic Mouse, see Use an Apple Magic Mouse.
Set additional zoom options.
Select “Smooth images” to make the zoomed screen images appear smooth.
Select “Zoom follows keyboard focus” to make the zoomed image shift to follow your cursor.
Click the “Zoom style” pop-up menu, then choose Full screen or Picture-in-picture.
When zoom is turned on, press and hold the modifier key or keys and scroll using your mouse to enlarge or reduce the screen image.