EM1x update on firmware 2 bird AF operation and settings
If you would rather head straight to a concise summary, the TL;DR is at the foot of the page — or jump directly to the FAQ.
If you are a happy user of an EM1x for birds in flight, you probably know a lot of the material in this post. But there are also a lot of things which are probably lurking in the back of your mind, or you might not have thought about the set-up strategy to get the best out of the camera system. This is an attempt to fix that by sharing my approach to the EM1x and firmware 2.0 operation when shooting birds in flight.
TL;DR
- EM1x firmware 2 AF settings: enable Bird-in-Flight AF with Zone select (small zone), C-AF+TR (continuous + tracking), and custom button for AF mode switching.
- Optimised settings: AF/MF lever to AF, AF Target Mode = Zone (small), C-AF+TR enabled, tracking response = Medium-Fast, focus area = Flexible/Custom.
- Shutter speed minimum: 1/2500s for takeoff/landing, 1/1600s for level flight at 300mm f/4 and ISO 200–400.
- Back-button AF on custom button: faster subject acquisition and mode switching compared to half-press shutter.
- ProCapture enabled: catches pre-shutter bursts for split-second moments; combined with firmware 2 AF = highly competitive with A9 and A6400.
Frequently asked questions
What is the difference between C-AF and C-AF+TR?
C-AF: continuous autofocus, but no predictive tracking. C-AF+TR: same, but adds Subject Tracking and Predictive Tracking. For birds, C-AF+TR is essential—the camera anticipates subject motion during shutter lag.
Should I use Zone select or Full AF?
Zone select (small zone) for birds in flight. Full AF area causes focus hunting and lags. Small zone forces priority on the bird; combined with tracking, it outperforms full-area AF.
What’s the optimal focus area for a small zone?
Flexible/Custom AF target mode with a small zone centred in the viewfinder. Allows repositioning the focus point with joystick while maintaining AF lock. More effective than fixed-centre AF for compositional flexibility.
How does back-button AF help?
Assigns AF activation to a custom button (not shutter half-press). Decouples focus from exposure—allows focus lock while recomposing without relocking focus. Faster mode switching and subject acquisition than shutter-button AF.
Is firmware 2 AF competitive with Sony A9 / A6400?
Yes. Firmware 2’s cross-type PDAF is now cross-type full-frame; Subject Tracking rivals Sony’s AF-animal detection. ProCapture adds 35-frame pre-capture—actually ahead of Sony for BIF. The gap has closed entirely.
