Buying advice: Old 2009-2013 iMac as a secondary screen for photo editing with Macbook Pro 2020

[GMShadow]

“Horrible” is relative, but I don’t think there are many people that think the iMacs’ displays are bad.

I personally think the display looks gorgeous compared to even new mid-range displays.

Even if they were 100% on spec when new, they'll have drifted over the last decade. And good brightness then is mediocre today.

 

[BeatCrazy]

I tested with a 2015 MB running Big Sur and it worked. So the source doesn’t need to be running Catalina or an older version of macOS. I was running Snow Leopard on the iMac FWIW.

Right but that's at least Intel. I get the impression that @hunk143 is using Apple Silicon.

 

[vaughas]

I have been using 2009 iMac 27" as second screen to MacBook Pro 2019 for Lightroom and Photoshop for 4 years with great success. iMac is turned on of course and Cmd + F2 toggle between screens. Absolutely no issues with the screen.

 

[afd]

Saw this on YouTube I think https://www.kickstarter.com/projects/juicycrumb/juicy-crumb-upgrade-logic-board unfortunately it’s a dead 2011 iMac with a 20.5” screen I have. Have also thought of stuffing a raspberry pi into it.

 

[jwbowk]

Hey everyone,

Brand new here, but I created an account just so I could post my experience with this. Thanks to a (fairly) simple workaround, it is feasible to use airplay to some of these older devices with fairly little lag.

I recently got a 2013 iMac that was heading to recycling at my workplace. I have a 2022 M2 macBook pro and wanted to use the iMac as an external monitor. The 2013 has four usb-a ports and two thunderbolt 2 ports. I bought a thunderbolt two cable, along with a thunderbolt 2 to 3 adapter and tried target display. Unsurprisingly, no dice.

I then saw some information regarding opencore legacy patcher; a program that allows you to force an upgrade to a newer macOS on an older device. Following the instructions on their website, I upgraded my 2013 iMac to Catalina (which allows you to set up an apple device as an airplay receiver). After upgrading, I was able to airplay to the device from my M2 macBook. However, over wifi, the lag was less than great and the resolution options were horendous. I tried connecting it with my thunderbolt cable and adapter before using airplay, but it did nothing.

I then found the following video. This guy did the same thing, but used a high quality usb-c to usb-a cable to connect his macBook to his force-upgraded iMac, and suggested that this would create a high quality connection. I tried this and, much to my surprise, it worked. I am now using a 2013 iMac as a monitor for my 2022 M2 MacBook. It works with any airplay device, even my iPhone 14 Pro. OCLP isn't too hard to get going if you have any prior knowledge of the apple boot menu.

NOTES:

• This will only set up a device to be used as an airplay receiver, not a universal monitor
• Take care choosing what OS you upgrade to. It could break certain things on your device, or may run like 💩 if you upgrade to the latest OS. My recommendation; only upgrade to Catalina if you're on an older device.
• Since it's airplay, it's best to use a wired connection. I tried using thunderbolt but it didn't help the connection. Had to use usb-c to usb-a.

TLDR:

To use an older iMac as a display:

1. install OCLP (Instructions on website)
   • Requires an external usb flashdrive with at least 16 gb storage (potentially more depending on the desired OS)
   • Follow OCLP download and install instructions. Will require some boot menu shenanigans.
2. Set up the device as an airplay receiver in settings.
3. Use high quality data transfer usb-c to usb-a cable to connect main device to iMac (credit to badSpade)
4. Cast to device using airplay

Hoping to save some people the hassle of buying and testing cables like I did, and help to make some informed decisions around this topic.

 

[badadoomtums]

Registered just to say thanks. Got a great deal on late 2013 iMac and found out there was no target mode. Had to look for Catalina downloads for a bit, as they don't appear in OCLP any more. Ordered adhesive strips, will try SSD swap shortly. Thanks again @jwbowk