Here is the Sony a9 II vs Sony a9 comparison that shows the highlights of the high-end FF mirrorless cameras.

Sony introduced the a9 II (Pre-order at B&H Photo Video), which adds a host of features for the working professional, along with a refined design largely borrowed from the a7R IV. Sony A9 II uses the same 24.2MP stacked CMOS sensor from the first a9, boasts the same 20fps black-out free shooting with the electronic shutter, and can perform the same 60 calculations per second with its blazing fast AF system.
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