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Apr 12, 2001
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Astropad's Luna Display accessory that's able to turn an old iPad or Mac into a secondary display for a primary Mac was today updated with a new feature that's designed to allow Mac-to-Mac mode to work over Ethernet and Thunderbolt.


The Luna Display is an alternative to Apple's Sidecar, allowing an iPad to be used as a display for a Mac. Unlike Sidecar, it works with other Macs, so you can use one Mac as a display for another Mac, something that's always been useful with machines like the iMac.

With a new 4.5 software update that's available today, the Luna Display can work with two Macs connected by Ethernet or Thunderbolt, which improves the Mac-to-Mac mode experience for users who have poor WiFi connectivity or would prefer to work with a wired connection. Prior to today's update, Mac-to-Mac mode was limited to the Luna Display's wireless connection.

The new software update brings other features including a battery indicator for a secondary device, secondary Mac keyboard enhancements, improved Retina support on M1 Macs, and for iPads, better compatibility with the 2020 iPad Air.

According to Astropad, Mac-to-Mac mode is an ideal alternative to Target Display Mode, a feature that Apple used to offer for older iMacs. Target Display Mode allowed an iMac to be connected to another Mac, with the iMac then serving as a display, but that functionality does not work with modern Macs.

The Luna Display allows an iMac to be used as a display for another Mac, but technically, it works with any two Mac combinations, so you can pair up two MacBooks, a Mac mini and a MacBook, or anything else.

The Luna Display is priced at $100 and can be purchased from the Astropad website.

Article Link: Luna Display's Mac-to-Mac Display Feature Now Works Over Ethernet and Thunderbolt
 
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JosephAW

macrumors 601
May 14, 2012
4,729
5,804
Wow I found a new use for my Mac Pro 1,1. :p
Now where’s my 23” Cinema Display to DVI adapter from my G5. :rolleyes:
 

sean+mac

macrumors member
Aug 13, 2020
85
120
Canada
Needs retina support before I'd spend money on it.
Thanks for the callout. I've been very low key aware of product for some time, and have mused that it'd be nice to use my iMac as a display for the MacBook in some rare cases. Your post encouraged me to open their website and it is surprisingly very light on any sort of clear specifications.

Hiding in the depths of the help docs was confirmation:
Luna currently supports the secondary iMac as a non-retina display. The primary iMac and other secondary Macs will still display in retina resolution. [source]
 

nilk

macrumors 6502a
Oct 18, 2007
679
228
Needs retina support before I'd spend money on it.
Yeah, I'd want proper support for my 27" iMac's 5k display, and have decent enough latency for typical office work (software dev in my case). Solutions I've tried (e.g. Duet) don't support the full resolution and look pixelated on the 5k display, and latency is bad enough that I don't want to use it, even over ethernet. And I could run a TB3 cable between my MacBook Pro and iMac if that helps.

Thanks for the callout. I've been very low key aware of product for some time, and have mused that it'd be nice to use my iMac as a display for the MacBook in some rare cases. Your post encouraged me to open their website and it is surprisingly very light on any sort of clear specifications.

Hiding in the depths of the help docs was confirmation:
That page was last updated Feb 3rd. I wonder if this latest release, with TB3 support can do iMac 5k resolution, and they just haven't updated the page? TB3 is enough bandwidth for that at least.
 
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apparatchik

macrumors 6502a
Mar 6, 2008
682
2,030
Cheaper to use JumpDesktop with the iPad to Mac mini, than spend $80 on Luna.

I suppose it depends on the use case, as a portable work setup, Luna's competition, Duet, might be the better alternative of the bunch for primary display, as it can be connected via usb-c cable, absolute minimum latency, no need to use a wireless network like you would with a remote desktop solution like Jump.

In any case, some interesting setups can be achieved with these solutions.
 

ignatius345

macrumors 601
Aug 20, 2015
4,597
6,519
Yeah, I'd want proper support for my 27" iMac's 5k display, and have decent enough latency for typical office work (software dev in my case). Solutions I've tried (e.g. Duet) don't support the full resolution and look pixelated on the 5k display, and latency is bad enough that I don't want to use it, even over ethernet. And I could run a TB3 cable between my MacBook Pro and iMac if that helps.

I'm in the same boat. If there was a viable* way for me to plop an M1 Mini behind my 2014 iMac 5K and use it as a display, I'd be all over it.

Odds are I'll nurse this thing along until Apple comes out with a proper successor, but it's nice to have options, especially if they save me a couple grand in the shorter term...

* low latency, full resolution
 

Darth Tulhu

macrumors 68000
Apr 10, 2019
1,838
2,975
Look at the bezels on that Air. Jesus.

It's inexcusable that it took Apple that long to get rid of them.

Anyhoo, this would be useful if it could turn my non-retina iMac 27 into a target display for an iPad Pro.

Not sure if any apps out there can do this, or whether or not it is possible.
 

cecil444

macrumors regular
Mar 9, 2008
156
210
NY
By the sound of it the Thunderbolt support is only for TB3/4 (i.e. the USB-C plug). Does anyone happen to know if this supports TB1 or TB2?
 
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reyesmac

macrumors 6502a
Jul 17, 2002
745
407
Central Texas
I heard it can't even do 1440p resolution. If it can't pull that off its not worth getting because you can just buy a monitor that can for not much more than the price of a luna dongle.
 

Mr Dobey

macrumors 6502
Aug 8, 2008
335
92
If only Sidecar supported horizontal flip 'teleprompter mode' all my needs would be met. M1 MacBook Air only supports one external monitor so Luna doesn't work for making an iPad Pro a third display teleprompter. Duet does fulfill this need but performance is not rock solid like Luna and Sidecar. The same problem persists with the new iMac. I hope the iMac Pro will have an M1X chip that supports more than Display + 6K Display.
 

MacBH928

macrumors 604
May 17, 2008
7,261
3,120
got to give it to Luna Display, they kept fighting even after SideCar was introduced. Not to forget Duet Display.
 
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niho

macrumors member
Dec 7, 2019
71
82
By the sound of it the Thunderbolt support is only for TB3/4 (i.e. the USB-C plug). Does anyone happen to know if this supports TB1 or TB2?
It should work with TB1/2 as well , since Thunderbolt standard between devices is just a network connection.

And the delay for Luna vs. Duet vs. Sidecar is?
For another @MR article on this...?
Duet air delay is similar to sidecar, not perfect, but very good if you're using 5G wifi or cable. Still, I wouldn't use any of them in long term. I've used at most 1440p @60fps , it was good.

I think Duet Air is subsciption
Yes, unfortunetely Duet Air is subscription $20 a year, not too bad to be honest. Performance is great, but it can be buggy sometimes. It can use Windows machines as screen as well. I used my parent's old laptop as second monitor while I was visiting them.
 

unchecked

macrumors 6502
Sep 5, 2008
293
315
If this finally pushes Apple to build in the function to allow us to repurpose old iMacs as external monitors for newer iMacs that we get then I’m all for it.
 
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