Back to Silas S. Brown's home page | X11 configuration

Mac magnification setup

OS X has built-in magnification under System Preferences / Universal Access. In 10.8+ it's System Preferences / Accessibility / Zoom. Here is my rhyme for remembering the keyboard shortcuts (on 10.8 the "invert colours" shortcut is disabled by default and needs to be enabled via System Preferences / Keyboard / Keyboard Shortcuts / Accessibility, and circa 10.11 they also disabled the zoom shortcuts by default and these now need to be re-enabled in the same way):

The Mac does not from Windows lift
these keys, so you should not press Shift.
But press Control, Command and Alt,
These three, with 8, a glare can halt.
And if the zoom be lacking whole,
then press these keys without Control.
For plus and minus take the same
as 8: the Alt and Option twain.

It appears that the image is processed as follows (at least in all versions up to 10.9):

  1. Text is anti-aliased onto a non-zoomed screen buffer
  2. The pixels are then mapped onto the larger zoomed buffer (which degrades quality if the zoom factor is not an integer)
  3. An additional "smoothing" step is optionally applied to the new image (I don't know if this step has knowledge of the original pixels, but it doesn't seem to have any knowledge of the original fonts).
The above steps acting in combination can blur the result. So my suggested settings are:

Speak selected text

On OS X 10.5+ you can enable a keyboard shortcut to speak selected text (defaults to Alt-Escape; press a second time to stop). This needs to be switched on in the text-to-speech preferences.

In 10.8, you need to take two additional steps to work around a bug: (1) change the keyboard shortcut (if you like the default, change it back again), (2) press "Play" to hear the voice's demo. The shortcut key will then work. (These additional steps were not needed in 10.5 through 10.7.)

The shortcut works in most native Mac applications, including Terminal, but not iTerm 1 or (some versions of?) Chrome.

Here is a script to change the voice from the command line (useful if you work in several languages).

"Linuxify" the Mac command line

Here is a script to make the Mac more GNU/Linux-like by: The script can be added to, or sourced from, your ~/.bashrc and/or ~/.bash_profile.

You may also want my Emacs configuration.

Using Safari "Reader" with zoom

The "Reader" feature of Safari 5.0, 5.1 and 6.0 doesn't work well with zoom because it uses a fixed-width layout which can easily be too wide for the zoomed viewport; this was fixed in 6.1 but if you're stuck with an old version you can try this reader narrowing script (requires administrator access to the machine) which also allows you to change the colours.

Safari 6.1's Reader fixed the width issue but doesn't allow colour changing (unless you invert the whole display in Universal Access); it doesn't respond to my stylesheets for low vision or to the above script.

Mac screen sharing with magnification

OS X has included VNC "screen sharing" since 10.4, but 10.7 introduced a feature that can make it hard for non-Mac VNC clients if your desktop size is not 1280x1024. One solution is to use an alternative VNC server, such as Vine (OSXVnc) which can be set to serve just one user session (can run on login with automatic login). Notes: Fundamentally it's still best to use a Mac desktop by connecting the display directly to the machine.
All material © Silas S. Brown unless otherwise stated.