Software/hardware solution to use 2019 iMac 27" as external display?

[IngaDW]

Hi there - I'll keep it short - thanks in advance for any recommendations.
I have a 2019 iMac 27" with 5K monitor. Is there a software or hardware solution so that a modern mac mini or MacBook air can use it as an external display? It needs to keep the colours true as it is used for scanning and processing artwork.

Longer version:
I know it is not natively supported - that's fine. But I will need to upgrade soon and the Studio Display is expensive, and for my needs, not as good as my current iMac display. It would be a real shame for me to have to downgrade my display to upgrade my computer.

 

[Tjmckay4]

I'm using a Luna display and a Thunderbolt 3 cable between my M2 MBP 14" and my 2017 iMac 27" (occasionally) and it's working pretty well.

Colours seem accurate and there's not too much lag as I'm using the Thunderbolt cable and not Wifi, which is terrible...

 

[IngaDW]

I'm using a Luna display and a Thunderbolt 3 cable between my M2 MBP 14" and my 2017 iMac 27" (occasionally) and it's working pretty well.

Colours seem accurate and there's not too much lag as I'm using the Thunderbolt cable and not Wifi, which is terrible...

Thanks for this - yes I've been learning about it too. A review on Amazon said the lag was still bad using Thunderbolt, which is a shame. Has that been your experience? How are the colours - are they preserved correctly?

"This device is a wonderful idea. I just upgraded from a 5k iMac to a Mac mini with a Studio Display. I wanted to use the iMac as a second monitor. I bought this hoping it would work well enough. Unfortunately there were too many issues to make it worthwhile for me.

First off the lag on the mouse movement is just enough to be infuriating. I read that you can use Wi-Fi, wired Ethernet, or Thunderbolt 4 to connect the two computers. I was already using wired Ethernet and figured that the jump from 1gbps to 40gbps for Thunderbolt 4 would help. It did not. At all.

Also, you can’t get the secondary monitor to go to sleep when the primary does. So when you’re not using the secondary monitor it just stays on unless you kill the Luna app and then put the computer to sleep using its own keyboard and mouse.

If they could fix these two main issues I’d love to try this again, but for now I gave up on this and returned it. I’m now using the old iMac as a standalone computer next to the new one and using Universal Control to use the same keyboard and mouse from the new computer on the old one. It’s much more responsive than the Luna was. It has its own disadvantages, but for me it’s a better option and it’s built into macOS Ventura.

Tech support was pretty good when I contacted them both before and after purchasing the Luna Display."

https://www.amazon.com.au/Astropad-Luna-Display-Extender-Wireless

 

[bobcomer]

I'll be trying Luna display in a day or two when it gets here.

Right now I'm using Duet Display, which is an all software thing. It works somewhat well, but the mouse lag is a thing with it too. It also gets confused if you have one of the machines on a KVM but not selected. I ended up with a connection for the display and mouse only, but the keyboard didn't work at all.

I really, really, want to be able to sometimes use my sweet iMac monitor for both my faster M2 Mac, and an i9 PC! I know it's never going to be perfect, but mouse latency is infuriating and I'm not sure why it would be that hard to fix.

 

[bobcomer]

Well, got the Luna Display in and the latency is less for me (forcing ethernet connection). It's more limited in what you can do than Duet Display. If you want to use one PC or one Mac use the iMac as it's display, it works pretty well. The iMac doesn't shut off its screen when the other machine's monitor does, but that's not a big problem. And you have to start the apps on both machines to connect. (there's no background functionality like Duet Display has.)

I, however, have 2 other machines I want to use the iMac as the display for, a Mac, and a Windows PC, and I may want to change at any time. Which makes Luna a total PITA, you have to move the dongle and restart the apps. That little dongle (that is hard to unplug it's so small and smooth) has to go on the source of the video's PC, not the iMac, so you have to move it between the other 2 PC's, and the target has to be a Mac, so I couldn't use my Windows PC's as a target too. Luna also doesn't have a default setting to makes it mirror the displays, you can do it but it's a pita.

Duet is a subscription model, Luna isn't. Neither are as good as I'd like. If Duet could get their latency down, it would be the best product. And if Luna could make that dongle work on the target PC and not the source, it would be the best.

 

[Nguyen Duc Hieu]

Hi there - I'll keep it short - thanks in advance for any recommendations.
I have a 2019 iMac 27" with 5K monitor. Is there a software or hardware solution so that a modern mac mini or MacBook air can use it as an external display? It needs to keep the colours true as it is used for scanning and processing artwork.

Longer version:
I know it is not natively supported - that's fine. But I will need to upgrade soon and the Studio Display is expensive, and for my needs, not as good as my current iMac display. It would be a real shame for me to have to downgrade my display to upgrade my computer.

HDMI to USB 3.0 video capture card.