Real Time Tracking and Animal Eye AF have been rolling out to Sony cameras since it has arrived in the Alpha a6400 in January 2019. The a7 III and a7R III got animal eye eye AF in April. Later on Sony a9 recieved this feature with firmware 5.0 and 6.0.
Sony RX10 IV costs around $1,699
Translated press text:
Software update contents:
1. Real-time pupil AF support for animals (still images only)
2. Real-time pupil AF operability improvement Support for half-pressing the shutter button
3. Improved operational stability
Scheduled release date for software updates:
Scheduled for 2019
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