The exchange happened in a different forum and was borderline off-topic. While I do not intend this to be a "cross-post" as commonly seen from folks fishing for information, I think that the members of this club would be interested.

So, I took a few days and I set up a little experiment to compare the MacOS version of X-Plane to the Windows version of X-Plane (on a Boot Camp partition), running on the same Mac.

My Mac is almost 8 years old and, while it was a good machine in its days, it is now borderline to run X-Plane. I was interested in anything that could get me some "free" extra frames per seconds (FPS). It would only be free because I had already purchased and installed a Windows 8.1 licence on a Boot Camp partition a few years ago. I will be upgrading to a new Mac in the coming months but I wanted to experiment before throwing the Windows licence in the garbage since it cannot be re-installed on another machine. The only cost is my time to conduct the experiment. Also note that the test vehicle is equipped with an AMD-made Radeon GPU.

So, I compared "apples to apples" (pun intended): same old Mac, same 11.05 X-Plane version (MacOS vs Windows), same plane, airport, runways, flight plan, screen resolution, X-plane settings, etc, no clouds or random weather, everything set-up to be all the same.

Out of the box, X-Plane ran better/faster in MacOS than the Windows version of X-Plane on the Boot Camp Windows partition. There was an average of 15% more FPS in MacOS. After updating and optimizing drivers, I was able to get the same rendering times for the GPU but the CPU still lagged a bit in Windows, for a 5-10% advantage to MacOS. That translated in only 1.5 to 3 more FPS in MacOS overall. Not significant but certainly not any FPS gain in Windows as previously suggested. Although not measured in any way that I can report, I found the quality of the graphics better in MacOS, even with the same rendering settings and screen resolutions. Must be due to the Boot Camp drivers. I could not establish any significant differences in load times between the two OS.

The experiment served me two ways. First, it reminded me how much I hate the Windows OS. I also feel confident that, if Mac is the machine of choice, running X-Plane on MacOS is the way to go.

The results may have been slightly different on a newer Mac with an updated CPU and GPU combination. At this point, I do not think that any difference would be significant and I do not think that I would invest in a new Windows OS licence to test it in my new Mac planned for this winter or spring. It was also suggested by another knowledgeable user that the results may be different if the Mac had a Nvidia GPU. I would be interested in hearing from someone that would have conducted a similar test with such GPU.

I did not compare to a PC. Why? Did I mention that I hate the Windows OS? ... and given the life expectancy of a computer, I will not have two depreciate at the same time. I do not think that anyone in this club would, but just in case, there is not need to suggest that the results would be better on a PC or that having a PC only for X-Plane would be the way to go... I am not throlling or wanting to debate the PC vs Mac thing. Just letting the users of this club know the results that I got, with the resources that I already had. Cheers.

Safety first: Keep it within the envelope, especially when flying in a room illuminated only by a computer screen...

Karl 

I am using a unmodified Imac and it runs X-plane 11 fine  

My Custom Scenery folder (249 GB!!) is full with airports I visited, many of them purchased and a bunch of landscape addons like Landmarks, Parks, continents like Alaska, Australia, New Zealand, Canadien Rockies, etc. Than further simHeaven continents, SFD Global and a lot of Mesh...

Is anyone of you able t to catalog how everything can work together properly and which conflicts can arise (e.g. overlapping)?

Has someone of you a better (and cheaper) solution for video recording on iMac without lost of high resolution?

Karl