Yeah, irritating, but iOS only reads the embedded "thumbnail" of RAF files. In this case it's 1920x1280 pixels.
The sad part is that macOS *does* support reading the actual 24 megapixel image. So Apple has the code, they're just not using it on iOS.
So please join me in letting Apple know that we'd like iOS to read the entire RAF files:
http://apple.co/FeedbackThe short request: Developers can only read the thumbnail from a RAF file using the ImageIO framework, but macOS can read the entire file. Please add this ability to the CGImageSourceCreateWithDataProvider / CGDataProviderCreateWithURL function on iOS.
I've also submitted this request via Apple's developer bug reporting tool.
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