Hi Jason,
Render times are specific to the scene and the given parameters in the render settings. Additionally to that the render hardware (each single component), which includes as well the network speed if Team Render is used. That is a huge mix, and certainly results in a longer discussion.
I rendered yesterday a single 5K image in 6:49 [h:m] and did not even thought about that it was long. But I can get also impatient for the same size if it is only an image that I convert (e.g., from equirectangular to a different projection method), and it takes a minute.
Given my use of a MacBookPro 17” (with a better cooling than the 15”), my experience is, they render fast on a very short time, and when they get hot, it becomes extremely slow, painfully slow. You didn’t mention the Drive.
16 GB might be too little as well, as the OS takes a lot away already, and in the moment it becomes virtual memory, things go slow even more. Open your Activity Monitor and see what happens.
Another question, what is the reason to employ Physical render at all for this. Most qualities that one need in 360ยบ are no depth of field and no motion blur, which are the main time eaters of the Physical Renderer. You might tell me what makes you use it.
Again, that is a long story and it is an individual one.
Typically render an empty scene, to see how fast that can be. It makes sense, as the file needs to be created and you see what time that causes alone.
Then use the simplest render setting, no AA and no textures, no shadows, standard render and only a few cubes in the scene, then render. Certainly no GI. Also here write down the time.
Use your final scene and render in the way you like, the time needs to be written down, as well.
Now use the simplest render setting, Standard, no AA and no shadows. No effects as in the two other ones. Compare the time. Big difference? Then you know already a little bit more.
Now go gradually with more and more specific render settings. ETC.
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The scene set up, is everything optimized, do you really need this amount of resolution in the models.
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I pretty much never use Ambient Occlusion, it is part of GI anyway. I see it often in the scenes I get since over 10 years, that people have it on even they are in early states of the set up, where this is completely a waste of time.
Depth of field, Motion Blur, Blurry reflections and transparencies, Caustics, Global Illumination and endless reflections, besides area shadows with high values, all of that slows one down.
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My best tip, don’t use anything you haven’t set up on your own! Use what is clear to you, light source and know all the over 100 parameters, use models that you have inspected if not modeled on your own, and optimized.
Use proper texture sizes, anything larger than needed slows the system down.
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There is much much much more, and it might seems endless. Get Cinebench and run it several times in a row until the fans of the Mac run constantly. Compare all the results. Google Cinebench for comparable results.
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As this can’t be a full list, and we had here and in Cineversity v1 [Archive] from time to time that question, you might find more answers there. Again I haven’t seen a complete list yet, and again, it is individual, often the scene is not optimized nor the render settings.
IF in doubt share the scene file here and I can check it, but that is not an offer for each day of course ;o)
My best wishes
