*Note: Buffer clearing times measured with a 64GB Lexar Pro 2000x UHS-II SDXC card. To minimize the effect of different lens' focusing speed, we test AF-active shutter lag with the lens already set to the correct focal distance.

Without EFCS, prefocused shutter lag increased dramatically 0.165 second, but with the fully electronic shutter, it was only 0.038 second. The Sony A9's prefocused shutter lag was only 0.020 second with EFCS, which is very fast. With the fully electronic shutter, manual focus shutter lag was 0.119 second. When manually focused, the Sony A9's shutter lag dropped to 0.097 second with EFCS, or 0.249 second without. With the fully electronic shutter, full AF shutter lag was 0.231 second, a little slower than with EFCS. With EFCS disabled, full AF shutter lag increased to 0.355 second.

This was with the mechanical shutter and electronic first curtain shutter (EFCS) enabled by default. The Sony A9's full-autofocus shutter lag (with the subject at a fixed distance) was good although not exceptional, measuring in at 0.216 second in Single-area (Center) AF mode with the Sony Zeiss 35mm f/2.8 lens. Time to capture, after half-pressing and holding shutter button.

Exiftool shutter count sony a7ii