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Luna Display Introduces Mac-to-Mac Mode Allowing Nearly Any Mac to Be Used as Secondary Display
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I find there is much less lag than using software remote desktop solutions. Also the biggest plus is the way LunaDisplay optimized the screen resolution on the remote device. Ive used Apple Remote Desktop and Chrome Remote Desktop and also various VNC clients and nothing compares to how smooth and high res the LunaDisplay works.
Im very happy with mine.
I've just tested Luna Display from a 2018 Macbook Air to a "Late" 2014 5k iMac (i7 quad core 32 GB RAM).
When using the 5K iMac as a secondary display with Luna Display, the following were my observations:
1. Moving a Pages window to the 5K iMac and typing in that Pages window:
The experience was smooth. I didn't notice any lag. The CPU utilization by the Luna Display app on the 2018 MacBook Air was below 10%. The CPU utilization by the Luna Display Secondary on the 5K iMac was below 5%. MacBook Air showed 6 Mbps of data being sent via Wi-Fi, which was the compressed signal sent by Luna from the MacBook Air to the iMac.
2. Playing a video stream from Sling TV (via Chrome), moving the Chrome window to the 5K iMac, and then going full screen in the Chrome window on the 5K iMac:
Video playing in the Chrome window (CNN feed) showed serious compression artifacts. The video quality was 4 or 5 on the scale of 1-10. The CPU utilization by the Luna Display app on the MacBook Air was 140% (this is a dual-core machine). The CPU graph showed all four threads being pegged to 80-90% or so. The CPU utilization by the Luna Display Secondary app on the iMac was 45% (which I believe is significant for a quad-core i7 machine). The MacBook Air was using 16 Mbps of data, which combined both the CNN feed via the Chrome browser window as well as the compressed video signal from the MacBook Air to the iMac.
3. Playing a 4K video from Youtube in a Safari browser window, moving the Safari window to the 5K iMac and then going full screen in the Safari window on the 5K iMac:
The 4K Video playing in the Safari window was somewhat jerky and there were some artifacts seen around objects due to compression.
4. Quickly Moving a System Preferences window across the secondary display (5K iMac):
The window movement was very jerky. It didn't look natural like one would expect in macOS. However, then I closed the Luna app on the 5K iMac, opened its own System Preferences window, and moved it from side to side for comparison. The jerkiness was still present when the window was being moved, but it was about 1/2 as jerky as when moving a window across the 5K iMac when it's used as the secondary display with the Luna app.
5. Using Luna Display Secondary app in a different space on the 5K iMac.
It's possible to create a new space and then open the Luna Display Secondary app in that space. Then, I was able to move between spaces on the 5K iMac, so I was able to see both the native apps running on the 5K iMac in their own space and the applications running on the MacBook Air and projecting on the 5K iMac (via Luna Display) in another space. However, the pointing device (in my case Magic Trackpad 2) connected to the 5K iMac worked only in the space where the Luna Display Secondary app was running. When I would switch to the other space on the 5K iMac, the mouse pointer was not present, so I couldn't control any apps running natively on the 5K iMac until I would close the Luna Display Secondary app on the iMac. So, as long as the Luna Display Secondary app was running, the only gesture that I was able to use on the Magic Trackpad 2 connected to the iMac in the space occupied by the iMac's native apps were swiping left and right between different spaces and also swiping up and down (for Exposé and Mission Control)
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In all of the above cases, the MacBook Air showed the access rate of Wi-Fi connection being 650 Mbps. The 5K iMac was connected to the network via Gigabit Ethernet. However, the signal sent from the MacBook Air to the 5K iMac never consumed more than 16 Mbps (and that included the Sling TV CNN feed played in a browser window).
IMHO, this Mac-to-Mac Luna display feature is only good for static or slowly refreshed windows like a text editor. It's not good for any video or photo editing or watching any video due to compression artifacts.
I would recommend that Luna makes it possible to adjust the compression ratio. When both Macs have plenty of available bandwidth to communicate with each other, lowering the compression ratio (at the expense of more data being sent between the two Macs) would improve the video quality and lower CPU utilization consumed by the compression on both Macs.
When using the 5K iMac as a secondary display with Luna Display, the following were my observations:
1. Moving a Pages window to the 5K iMac and typing in that Pages window:
The experience was smooth. I didn't notice any lag. The CPU utilization by the Luna Display app on the 2018 MacBook Air was below 10%. The CPU utilization by the Luna Display Secondary on the 5K iMac was below 5%. MacBook Air showed 6 Mbps of data being sent via Wi-Fi, which was the compressed signal sent by Luna from the MacBook Air to the iMac.
2. Playing a video stream from Sling TV (via Chrome), moving the Chrome window to the 5K iMac, and then going full screen in the Chrome window on the 5K iMac:
Video playing in the Chrome window (CNN feed) showed serious compression artifacts. The video quality was 4 or 5 on the scale of 1-10. The CPU utilization by the Luna Display app on the MacBook Air was 140% (this is a dual-core machine). The CPU graph showed all four threads being pegged to 80-90% or so. The CPU utilization by the Luna Display Secondary app on the iMac was 45% (which I believe is significant for a quad-core i7 machine). The MacBook Air was using 16 Mbps of data, which combined both the CNN feed via the Chrome browser window as well as the compressed video signal from the MacBook Air to the iMac.
3. Playing a 4K video from Youtube in a Safari browser window, moving the Safari window to the 5K iMac and then going full screen in the Safari window on the 5K iMac:
The 4K Video playing in the Safari window was somewhat jerky and there were some artifacts seen around objects due to compression.
4. Quickly Moving a System Preferences window across the secondary display (5K iMac):
The window movement was very jerky. It didn't look natural like one would expect in macOS. However, then I closed the Luna app on the 5K iMac, opened its own System Preferences window, and moved it from side to side for comparison. The jerkiness was still present when the window was being moved, but it was about 1/2 as jerky as when moving a window across the 5K iMac when it's used as the secondary display with the Luna app.
5. Using Luna Display Secondary app in a different space on the 5K iMac.
It's possible to create a new space and then open the Luna Display Secondary app in that space. Then, I was able to move between spaces on the 5K iMac, so I was able to see both the native apps running on the 5K iMac in their own space and the applications running on the MacBook Air and projecting on the 5K iMac (via Luna Display) in another space. However, the pointing device (in my case Magic Trackpad 2) connected to the 5K iMac worked only in the space where the Luna Display Secondary app was running. When I would switch to the other space on the 5K iMac, the mouse pointer was not present, so I couldn't control any apps running natively on the 5K iMac until I would close the Luna Display Secondary app on the iMac. So, as long as the Luna Display Secondary app was running, the only gesture that I was able to use on the Magic Trackpad 2 connected to the iMac in the space occupied by the iMac's native apps were swiping left and right between different spaces and also swiping up and down (for Exposé and Mission Control)
------------
In all of the above cases, the MacBook Air showed the access rate of Wi-Fi connection being 650 Mbps. The 5K iMac was connected to the network via Gigabit Ethernet. However, the signal sent from the MacBook Air to the 5K iMac never consumed more than 16 Mbps (and that included the Sling TV CNN feed played in a browser window).
IMHO, this Mac-to-Mac Luna display feature is only good for static or slowly refreshed windows like a text editor. It's not good for any video or photo editing or watching any video due to compression artifacts.
I would recommend that Luna makes it possible to adjust the compression ratio. When both Macs have plenty of available bandwidth to communicate with each other, lowering the compression ratio (at the expense of more data being sent between the two Macs) would improve the video quality and lower CPU utilization consumed by the compression on both Macs.
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Resolution was 5K but only still images were usable. Read my review above.
Is general browsing in browsers workable in this setup? How smooth is vertical page scrolling at normal speed?
I don't have the setup anymore, as I returned the dongle because it was not a workable solution for my use case. The scrolling was not as natural as it was natively.
Generally, I wouldn't rely on this as a solution for a 5K monitor. If you have a 5K iMac, why not use it as the actual computer instead of beaming the image from another Mac? If you want a 5K monitor, just sell your iMac 5K and use the money to pay toward a 5K monitor.
IMHO, Luna could reduce the compression ratio and the CPU utilization at the expense of higher bandwidth utilization for the projected video. Unfortunately, the compression ratio is too high and is not adjustable at this time; hence, the bandwidth is underutilized, the CPU is overutilized, and the image suffers from the high-compression-ratio artifacts.