Despite the relatively large size of the 100-400, that lens has an exceptionally fast twin-linear autofocus motor, which allows it to acquire and track subjects with a surprising level of speed and accuracy.
Today, I want to highlight how well it performs as a video action lens when shooting quick subjects.
During the same enduro bike race I mentioned in my previous post, I also shot a number of slow motion videos with the X-T4 and XF100-400mm lens, using the FULL HD HIGH SPEED REC feature that’s found in the X-T4’s video menu. (This setting is found on all of the current X Series, including the X100V.)
Shooting in tight quarters with the 100-400 lens, I captured a number of scenes at 1/2 and 1/4 time, and I was amazed at how well the camera and lens locked onto and tracked the subjects through the frame, even when I quickly swing the lens around to grab the racers as the rode by me.
Given that telephoto lenses effectively magnify distance, which means the camera has to work even hard to follow the focus, this is a testament to just how good the 100-400 is for shooting fast subjects.
X-T4 Autofocus Settings for Shooting Action
In the X-T4’s MOVIE MENU, I kept the MOVIE AF MODE set to “MULTI,” with FACE DETECTION set to ON. The combination of these allows the camera to do the heavy lifting and choose what to focus on.
For more manual control over focus when shooting movies you’d want to switch the MOVIE AF MODE to “AREA.” This setting allows you to move the little green focus box around the frame via the AF joystick.
In addition to showing you just how capable the X-T4 and 100-400mm lens are for shooting sports and fast moving subject, it’s just a really fun mountain biking video with a cool soundtrack.