Here's a test of the Nikkor 180-600mm lens with a Nikon 1.4x Z teleconverter and the Nikon Z9 shooting 120 fps video in 4k N-RAW. When viewing in slow motions, you will see the camera/lens occasionally refocusing to keep up with the hummingbird's movement but this is expected and quite normal to see with any camera. In real time, you would not see these focus acquisitions as they occur very fast. The Z9 accurately finds and reacquires focus on the bird's eye.
The footage was taken on a cloudy day and was shot at ISO 4000 which is the second native ISO using the Z9 with NLOG. Shutter speed was 1/250 sec. Aperture was f/9. Shot at 840mm. Slight noise reduction and sharpening applied to footage.
The hummingbird is a Ruby-Throated Hummingbird (juvenile male).
Music: Licensed via Sound Stripe. Song: The Diary Instrumental by CJ-O.
