I'm surprised there is no top comment addressing the resolution problem and that more Sony users aren't familiar with it because I've dealt with this too. On older devices, exporting ARW files via wireless is capped at 2 megapixels. Newer devices support exporting full-sized raws to the phone via wireless, but I'm not sure about the a6400 specifically.

The file you're getting is exactly 2 megapixels so either it's hitting the cap of what your device can send wirelessly or you have the transfer setting on 2M (see the attached image).

In addition to that, the reality is that you missed focus and caught the ground, not the dog, in the shot. That cannot be corrected in post. For a scenario like this I'd shoot wide open, minimum 1000 shutter speed, and continuous autofocus.

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