Did I miss something or is the tone mapper not released yet? I admit I'm multitasking here, but just have an exposure slider in the image lab (or whatever it's called).
Sidebar: I kinda miss when Halide's driving purpose was rapid launch and simplicity. I would almost prefer a zoom function to all of this HDR gymnastics (though, to be clear, Halide is my most-used and most-liked camera app).
EDIT: Ah, I see, it's a Mark III feature. That is not REMOTELY clear in the (very long) post.