Apple, You Make It Hard: Mac Laptop “Retina” Screen Update #amwriting

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:

  1. Start from an account for which you have admin privileges.
  2. Open the Terminal app (you can find it in Applications/Utilities)
  3. Copy and paste the following command: sudo defaults write /Library/Preferences/com.apple.windowserver.plist DisplayResolutionEnabled -bool true
  4. Press return. Terminal will ask for your admin password. Provide it and press return.
  5. Restart your Mac.

Now HiDPI (AKA “Retina”) resolutions should be available in the SwitchResX menu, assuming your laptop screen is capable. Enjoy!

If you’ve never used Terminal before, here’s a quick breakdown of what’s happening in its screen.

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.

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How to Give Your Older Macbook Air a “Retina” Screen

I don’t know about you, but I have a severe technology envy problem. I look at tech specs of new Apple products and heave deep, heartfelt sighs. In particular, I would very much like a newer Macbook 12 instead of my older Macbook Air 11. It’s… well, it’s lighter. To a former aerospace engineer, 5.6 ounces saved is 5.6 ounces, man! Think what you can boost with an extra 5.6 ounces to spare for fuel!

You can get Retina-style resolution on your older Macbook Air.

Not only that, but it has that nice, crisp Retina screen. Reading on the normal resolution Macbook Air 11 with a pixel density1 of 135 DPI—sometimes I take off my glasses and look at the screen from a distance of six inches (I’m very nearsighted) in order to read something. It doesn’t always help. The Retina displays on my iOS devices show text that is more crisp, and have more detail in the graphics.

I discovered a way around the lack of a “Retina” display quite by accident. Here’s my secret:

SwitchResX $16 USD (free trial available)

SwitchResX is a utility designed to give its users far more control over monitors and their resolutions than Apple is willing to provide. Bluntly, it has a lot more complexity than I’ll ever need, and I’m comfortable with tech (see above.) But for $16 it gave me a Retina screen equivalent for my Macbook Air, without delving into the tech details further than an added menubar icon.

UPDATE 2018-12-20: In addition to the below, you may also need to enable HiDPI on your Mac system. If no “HiDPI” resolutions show up when you use SwitchResX, check out Apple, You Make it Hard: Mac Laptop “Retina” Screen Update

You’ll need admin privileges on your account to install it. For these purposes, you’ll only need to set two of its preferences (open System Preferences; tap on the SwitchResX icon towards the bottom of the screen.) Be sure that its menubar extra is enabled (SRX menus prefs), and that the “SwitchResX daemon” is set to Launch on login (SRX general prefs). Close the SRX prefs window and quit System Preferences.

Now click on that new menubar icon that looks like a screen. You should see a long list of resolutions that you never knew your Macbook Air had available. Select the largest one that says “HiDPI” next to it, and you’re in business! (Note that if you have a Macbook Air 13 you’ll probably want one that’s in a 16:10 ratio, and for a Macbook Air 11 you’ll want 16:9.)

For the Macbook Air 11, that’s a DPI in HiDPI mode of 253 pixels per linear inch, higher than the Macbook Pro 13’s 220 DPI in Retina mode.

Enjoy your rejuvenated Mac!

(Note that I still envy Macbook 12 owners—after all, they have Macbooks that are 5.6 ounces lighter than mine. I just don’t envy them as much.)


  1. A note on resolution, pixel density, and what “Retina” means: Resolution, as commonly used these days, means the number of pixels horizontally and vertically on a screen. Thus, the Macbook Air 11 has a maximum resolution of 1366 x 768 pixels. This is a measure of how much information the display can present.

    Pixel density, on the other hand, is a measure of how crammed that information is. 135 DPI is pretty darn crammed for a normal monitor. My LG Ultrawide 25UM58 monitor (also normal) has a maximum pixel density of 111 DPI, and the pre-Retina Macbook Air 13 has 128 as its nominal max.

    “Retina” in Apple parlance is much the same thing as “HiDPI” in Windows terminology. Each means that four physical pixels are used to display each “logical” pixel. So at least in terms of how much text can be displayed at a given point size, the “resolution” is diminished by a factor of two in each dimension. That text will be far more crisp and easy to read, however.

    Windows is more honest about this (IMO): Apple will describe a “2560-by-1600 (Retina)” resolution, which means the same thing as Windows “1280 x 800 HiDPI”. Both screens will display exactly the same amount of sharp Times New Roman 12 point text.