In November, I wrote about giving your older Mac laptop a “Retina” screen by enabling it with SwitchResX. Well, I just upgraded my MacBook Air 11 to Mojave (MacOS 10.14.2) via a “clean install”, and it took away my beautiful high-resolution, pseudo-Retina screen! As an obsessive nerd, I could not possibly let that one stand.
It seems that years and years ago, I installed Apple’s dev tools, which enabled HiDPI (pseudo-Retina), unbeknownst to me. When I did a clean install of Mojave, I wiped out both the tools and the HiDPI capability. Oops.
Long story short, I found what I needed in this article, “How to Enable HiDPI Mode in Mac OS X,” by Jim Tanous. Here’s a summary of how to enable these delightful screen modes:
- Start from an account for which you have admin privileges.
- Open the Terminal app (you can find it in Applications/Utilities)
- Copy and paste the following command:
sudo defaults write /Library/Preferences/com.apple.windowserver.plist DisplayResolutionEnabled -bool true - Press return. Terminal will ask for your admin password. Provide it and press return.
- Restart your Mac.
Now HiDPI (AKA “Retina”) resolutions should be available in the SwitchResX menu, assuming your laptop screen is capable. Enjoy!
N.B.: This works because of two effects: SwitchResX enables you to go to a scaled resolution larger than the largest “native” resolution on many monitors (AKA “stretched” resolution)—including the MacBook Air 11 built-in monitor. Enabling HiDPI enables you to use a “half-resolution” or HiDPI. Thus, the text is four times sharper because it uses four times as many pixels to render text. With both these effects in place, I can get a 1280×720 “Retina” resolution on my old MacBook Air 11. If a monitor can’t display a stretched resolution, the best it can do for a HiDPI is half the resolution of the maximum native resolution. For example, this doesn’t do much of anything for my LG Ultrawide, which can’t display a stretched resolution. So results are entirely dependent on what SwitchResX can do with your display hardware.
