When the new M1 iMacs launched, we wrote about Target Display Mode being absent from the hardware. While Luna Display has offered a wireless alternative that works with all Macs for some time, a new update today essentially brings back Target Display Mode with Ethernet and Thunderbolt support, with one limitation.

As a refresher, Target Display Mode was last supported in the mid-2014 iMacs and earlier (non-Retina models) and Apple officially killed the feature with macOS Mojave and later. It allowed the use of a Mac as an external display, powered by another Mac.

We previously highlighted Astropad’s Luna Display and its Mac to Mac mode as a great workaround to get the functionality of Target Display Mode but until today, it only worked over a wireless connection. Now with Luna Display 4.5, the software supports wired connections over Ethernet or Thunderbolt just like Target Display Mode did.

Previously, Mac-to-Mac Mode only worked over Luna’s wireless connection. With today’s update, Mac-to-Mac Mode will also support Ethernet and Thunderbolt connection between Macs, with a seamless set-up process.

This will improve the Mac-to-Mac Mode experience for users with limited WiFi connection or who prefer not to connect wirelessly, as they’ll now have the option for a wired connection.

We double-checked with Astropad and its $99 hardware adapter is still required when using Luna Display’s Mac to Mac mode over Ethernet or Thunderbolt. It supports recognizing the second Mac as a display, GPU acceleration, and reliable performance.

However, one limitation, for now, is a secondary iMac is limited to non-Retina resolutions. But Luna Display is looking into offering 4K/5K support (keep in mind Apple never offered Target Display support for its Retina iMacs).

Luna Display 4.5 release notes:

  • Mac-to-Mac Mode now supports Ethernet and Thunderbolt connection between Macs
  • Primary Luna app now shows a battery indicator for the secondary device
  • Secondary Mac keyboard enhancements: key repeats are properly working
  • Refreshed macOS app icons
  • Retina support on M1 is more reliable now
  • In the iOS app: enhanced compatibility with 2020 iPad Air 
  • General bug fixes and improvements

If you’re wanting to try out a setup like this without committing to the hardware purchase, Duet Display is another option with Mac to Mac and wireless as well as wired support.

Top image via Phillip Caudell

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