Sony’s eye AF technology has revolutionized autofocus, providing incredible focusing capabilities for portrait photographers. But how well does it work on fast moving and erratic subjects like birds in flight? In this in-depth article, we’ll examine if Sony eye AF is up to the task of bird photography.
How Does Sony Eye AF Work?
Sony eye AF made its debut in 2016 with the Sony A7R II camera. It uses advanced image recognition and machine learning to detect and lock focus on a subject’s eyes.
Here’s a quick rundown of how Sony eye AF works:
– The camera uses its image sensor and image processing engine to analyze the scene. It looks for shapes and patterns that match a human eye.
– When it detects an eye, it applies a focusing box over the eye. This is the eye AF system at work.
– The camera will then engage continuous autofocus to track the eye as it or the camera moves. The eye remains in focus as long as it is detectable.
This technology made photographing portraits much easier, as you no longer had to manually focus on the eyes. The camera could handle it for you automatically.
Sony has included eye AF in many of its mirrorless cameras like the popular A7 III and A9 series. The AI-based system has evolved over time to become faster and more accurate with each new camera generation.
Advantages of Eye AF for Bird Photography
On paper, Sony’s eye AF system sounds very promising for capturing sharp bird photographs:
– Fast focusing – Birds move extremely fast, especially in flight. Sony eye AF can rapidly focus on the eye in as little as 0.02 seconds. This is essential for freezing fast action.
– Automatic tracking – Sony eye AF will automatically track a subject’s eye as it moves around the frame, as long as the eye remains detectable. You don’t have to manually move the focusing point.
– Increased accuracy – For portraits, shooting at the eye is critical for getting the subject in focus. The same applies to bird photography. Sony’s AI technology can focus precisely on the eye.
– Enhanced hit rate – With difficult subjects like birds in erratic flight, you aren’t going to achieve 100% in-focus shots. But eye AF should help obtain a higher percentage of sharp images and fewer misses.
– Better frame coverage – Eyes located anywhere in the frame can be targeted. With birds, you don’t always compose dead-center, so expansive coverage is an asset.
For these reasons, Sony eye AF has the potential to make bird photography much easier and more effective compared to manually focusing on the eye. But how well does it work in real world practice?
Sony Eye AF Bird Photography Settings
If you want to use Sony eye AF for birds, start with these camera settings for the best chance of locking focus:
– AF Mode: Choose Continuous AF
– Focus Area: Expand Flexible Spot or Zone is ideal – wide enough to detect eyes, but targeted enough for precision
– Drive Mode: High speed burst like 10-20fps to capture fleeting moments
– Metering: Center-weighted average metering works well
Next, map the custom AF-On button to Eye-AF so you can instantly activate it when a bird is in frame.
Set your camera to high speed burst mode and fire away when a bird enters the scene. The camera will attempt to detect and lock onto the eye. This technique takes some practice, but allows the camera to track focus on erratic birds.
You may need to use manual focusing for perched or stationary birds. But for in-flight action, Eye-AF has a big advantage.
Does Sony Eye AF Work on Small, Distant, or Fast Moving Birds?
Bird photography presents some challenges that can hinder the eye AF system:
Small birds – Smaller birds like songbirds have very tiny eyes. This gives the AF system less to work with when detecting and focusing on the eye.
Distant birds – Birds photographed against blue skies from a distance also appear very small in the frame, again limiting the camera’s ability to pinpoint the eye.
Fast moving birds – Birds in rapid flight can move across the frame in the blink of an eye. This tests the speed and tracking capability of the AF system.
Erratic movement – Birds make quick erratic movements in the air. It’s hard for the AF to keep up with and predict this behavior.
Obstructions – Branches, leaves, grass, and other objects can come between the camera and the bird, obstructing the view of the eye.
Low light conditions – Eye AF performance diminishes in low ambient lighting, like at sunrise and sunset when birds are most active.
Backlit birds – Birds backlit against bright light are essentially reduced to silhouettes, giving the AF system almost nothing to lock onto.
These conditions make it quite hard for even advanced eye AF technology to successfully work on birds. Next we’ll see how well Sony cameras perform in the real world.
Sony Eye AF Bird Photography – Real World Results
To evaluate real world Sony eye AF performance on birds, we will examine sample images and autofocus hit rates from three camera bodies:
Sony A9 II – Sony’s flagship sports-oriented full frame mirrorless camera.
Sony A7R IV – High resolution full frame camera tailored for image quality.
Sony A6600 – Crop sensor mirrorless camera with lightning fast focusing.
Sony A9 II Eye AF Bird Photography
The Sony A9 II has state of the art autofocus with 693 phase detection AF points covering 93% of the frame, and real-time eye AF for humans and animals. This makes it one of the top performers for bird photography.
In ideal conditions with good light, large birds, and unobstructed views, the A9 II can achieve tack sharp focus on a bird’s eye near 100% of the time. AF speed is nearly instantaneous.
But for small, distant, or fast moving birds, keeper rates can drop to around 40-60%. Still, this hit rate surpasses what is possible manually focusing.
Sony eye AF gives you a fighting chance at capturing super telephoto bird images like this:
Image: Lensmate
Even with large lenses like the 600mm f/4, the A9 II will tenaciously lock onto the eye and nail focus with a high degree of accuracy.
For extreme distances, using the Clear Image Zoom feature gives added reach while maintaining quality.
Image: Sony Alpha Universe
Here eye AF still provides sharp focus at over 1000mm equivalent magnification. Useful for tiny birds, though noise increases with extreme cropping.
The A9 II provides the best chance of achieving tack sharp bird photos with eye AF when lighting and distance allow the system to work reliably.
Sony A7R IV Eye AF Bird Photography
The 61 megapixel A7R IV has a hybrid AF system with 567 phase detect points and 425 contrast detect points covering 74% of the sensor. Combined with real-time tracking and 10fps burst shooting, it’s Sony’s highest resolution body capable of bird eye AF.
Hit rates are lower than the A9 series, but the R IV impresses with its ability to crop in massively while retaining excellent detail:
Image: Cameralabs
Even with a 150-600mm lens, the 61MP sensor allowed massive cropping to nail focus on this small puffin’s eye.
The A7R IV struggles with erratic motion blur at longer focal lengths. Using faster shutter speeds is recommended, even if it means pushing ISO.
All things considered, the A7R IV does a remarkable job focusing on small details like bird eyes. It’s not designed for action like the A9 II, but provides safety through aggressive cropping power.
Sony A6600 Eye AF Bird Photography
The APS-C sensor Sony A6600 houses 425 phase and contrast detection focus points covering 84% of the frame. With industry-leading focusing speed of 0.02 seconds and real-time eye AF, it’s Sony’s most capable crop sensor camera.
Pair it with APS-C lenses like the Sony 70-350mm, and the 1.5x crop factor gives a 525mm equivalent reach.
For larger birds, the A6600 will reliably hit focus on eyes even at maximum zoom:
Image: Switchback Travel
The smaller APS-C coverage area makes eye detection more effective on distant birds compared to full frame cameras.
For small songbirds however, keep your distance expectations in check. The A6600 can struggle beyond about 10-15 feet.
Used within its limits, the Sony A6600 offers pro-level focusing at a more budget friendly price point.
How to Improve Sony Eye AF Bird Photography Hit Rates
While Sony eye AF technology is extremely capable, it doesn’t guarantee perfect in-focus bird shots. Here are some tips to boost your keeper rate when photographing our feathered friends:
Good light – Shoot in bright, even lighting. Overcast days are ideal. Avoid low light at dawn and dusk.
Clear backgrounds – Compose with a clean background. Busy backgrounds make AF more difficult.
Allow space – Frame the subject with extra room to allow for erratic movement.
High burst rate – Use the fastest burst mode to increase chances of sharp frames.
Pre-focus – Pre-focus on a spot where you expect the bird to be. This gives a head start.
Quick shutter response – Use high speed mechanical shutter to instantly freeze motion.
Manual focus for perched birds – Use magnified live view and peaking to fine tune focus on stationary subjects.
AF tracking options – Try toggling between Lock-On AF options to handle erratic motion.
No technique is guaranteed. But using the best practices above will help you push the capabilities of Sony eye AF to its limits for bird photography.
Sony Eye AF vs Manual Focus for Birds
Is it better to use Sony eye AF or manual focus for capturing tack sharp bird portraits and in-flight action? Here’s a comparison of the two techniques:
Sony Eye AF Advantages
– Lightning fast focusing
– Automatic tracking of eyes
– Frees you up to compose shots
– High fps burst increases chances of sharp images
– Makes bird photography accessible to beginners
Manual Focus Advantages
– Accuracy in challenging situations
– Focus peaking and magnification for precision
– Better for perched and stationary birds
– More control and no chance of wrong AF lock
There is no definitive answer. Both methods have pros and cons.
In ideal conditions, Sony eye AF delivers fast, accurate, in-focus bird shots with an incredibly high keeper rate. It’s especially useful for unpredictable birds in erratic flight.
But seasoned bird photographers may still prefer manual focus for control and precision in challenging situations.
A balanced approach using both auto and manual focus is recommended to master bird photography with Sony mirrorless cameras.
Conclusion
Sony’s eye AF technology is an impressive innovation that makes bird photography more achievable than ever before. But it’s not infallible technology.
For large, unobstructed subjects in ideal lighting, eye AF results can be spectacular on cameras like the A9 II. Expect near perfect focus lock with fast moving birds.
But small, distant, fast moving birds still cause issues. In these cases manual focusing has better accuracy.
Practice using eye AF and manual focus together for best results. Use the right AF mode for the situation. This will help you maximize keepers and capture perfectly focused bird photos.
Sony continues to rapidly iterate and improve eye AF tracking. More advanced algorithms and sensor resolutions will only make bird eye AF more reliable on future cameras.