Can iMac 2020 or iMac 2011 be the second monitor of Mac Studio 2023 ?

The Mac Studio and the 2020 iMac do not support Target Display mode in any capacity.

You may be able to use the AirPlay to Mac option with the 2020 iMac, for content that does not require fast refresh rates or zero lag. Static content such as spreadsheets or documents for example.

click here ➜ Set up your Mac to be an AirPlay Receiver – Apple Support

Then from control center on the Mac Studio, you should be able to click on Display ➜ Display Settings, and then find the 2020 iMac in the [+] dropdown to connect to. Once connected, you can set it as mirrored or extended display. To set it as Extended, select the "Stop Mirroring Option" from the drop down.

The answer is No, as far as hardware display connections. The 2011 iMac is the only Mac you have that supports acting as a TDM display – but the other Macs are both too recent to support using it.

If your 2020 iMac is running macOS Monterey or later, you could set it up as an AirPlay Receiver – and use it as an AirPlay screen for the Mac Studio. The Studio would still need at least one real hardware monitor. It sounds like it would also be possible to make the Mac Studio act as an AirPlay Receiver for the 2020 iMac (not at the same time).

Set up your Mac to be an AirPlay Receiver - Apple Support

System requirements for Continuity features on Apple devices - Apple Support

HC521 wrote:

But I found it's interesting that my Mac Studio mouse can control iMac 2020 but no files can be dragged into the iMac

Apple has a bunch of features that they group under the Continuity umbrella. So many that it's a bit hard to keep track of them all.

Work seamlessly across all your devices - Apple Support

System requirements for Continuity features on Apple devices - Apple Support

I think the particular one to which you are referring is Universal Control . Apple mentions dragging files from one Mac to another, or from a Mac to the Files app on an iPad … but not dragging files from the iPad to the Mac.

You need to carefully read what Apple says in Target Display Mode. A 2020 iMac will simply not work in Target Display Mode.

Argue and wish all you want however we have gone through this hundreds of times with similar wishers as you and the answer is always the same, it will not work. Not only is the 2020 too new Target Display Mode simply does not work on any Apple M series CPU based machines.

HC521 wrote:

This really helps. It is making my iMac 2020 as a second monitor.

But one thing, after I make it as an extended screen, iMac 2020 looks really blurry although it is 5K Retina.

Is there anyway to adjust the quality?

Thank you so much!

There might be no way to make AirPlay to Mac take full advantage of the 5K resolution of your iMac's screen.

I skimmed a long thread on another forum where people were trying to figure things out. It sounds like AirPlay might only support a few resolutions:

• 3840 x 2160 – only with the newer AirPlay protocol supported by Monterey
• 2560 x 1440 – only with the newer AirPlay protocol supported by Monterey
• 1920 x 1080
• 1280 x 720

These are not Retina resolutions. That is, to say, if you picked "2560x1440" as an AirPlay resolution on your Mac Studio, the Mac Studio would not just use that as a sizing guideline, doing the actual drawing at a 5120x2880 level. It would send over a 2560x1440 signal. The 5K iMac acting as an AirPlay Receiver would stretch the picture but without the benefit of being able to use its higher resolution to fill in detail. Same for "3840x2160".

When you are using Retina "like 2560x1440" mode on a 5K iMac or a 5K Apple Studio Display, your applications are drawing at 5120x2880 pixel level. But in those cases, you are also talking about a high-bandwidth hardware connection (internal connection, or Thunderbolt 3 connection) from the computer/GPU to the display.

You may need to set the display resolution for the 2020 iMac to something other than what it defaulted to through AirPlay.

Click on the iMac 2020 display image in System Settings ➜ Displays on the Mac Studio, and change the resolution, and see what looks better.

No recent Mac can use Target Display Mode, there are software solutions like Luna Display.

As mentioned the answer is "no", in short you need to buy an external display to work with your new Mac Studio. Enjoy the Studio, its a great machine!