Last week's goal was to put a significantly challenging subject in front of the Sony Alpha a1's AF system.
This project started with 350+ images of whitetail deer captured with the outstanding Sony FE 600mm f/4 GM OSS Lens. At f/4, this lens produces a shallow depth of field that presents an AF challenge. Initially, the deer were milling about (erratic motion), but the game was quickly upped when a large group of deer came in fast, primarily single file, leaping toward the camera position. With animal eye detection and the entire AF area selected, the a1 easily and impressively tracked these subjects' eyes and produced an extremely high in-focus rate, including when the deer were leaping at close distances.
Despite the in-focus aspect of the image, none of these pics were worth keeping as the deer were shedding their winter coats and looking shaggy. I needed pictures that would look good in a review. From a wildlife perspective, birds, primarily ducks, were the acceptable subject I had access to.
After watching the weather forecast and the migration reports for some hotspot locations within driving distance, I made a final decision. On this day, the temperature was going well above freezing, and clear skies were forecasted. Bright sunlight brings out birds' iridescent colors, and the sky color reflects in the water, which, in this case, provided a surrounding blue color in the image (deep blue late in the day). The wind speed was supposed to be light for calmer water. The temperature was going to be comfortable — sitting in the water in the wind and sub-freezing temperatures complicates duck photography.
On this morning, I drove to the closest of the four selected locations, about 2.5 hours away. Unfortunately, the perfect subjects, the wood ducks reliably found there, were not there. While Canada geese were plentiful, I was looking for something different.
Plan B was immediately implemented. The Chesapeake Bay location was 2+ hours farther away, but this location is best in the afternoon, so there was still time to make it there for the ideal lighting.
Upon arrival, I discovered that the huge winter flock of ducks was down to a small fraction of the count. I expected a reduced count, but not this reduced. Fortunately, a selection of the ideal species was there, and with fewer birds, it was easier to isolate individual subjects, making the situation was ideal.
The scenario was ideal except for some wind that made the water choppy. Ideally, swimming duck photography is done at the water level, with the camera just above the water. This low camera position provides a side view of the duck, with a more-distant background, meaning the background has a stronger blur, making the subject pop.
When photographing floating ducks, getting the camera low involves sitting in the water, with chest waders and thick insulated pants required at this time of the year. With the high-frequency wind chop, splashing salt water was an issue, requiring a slightly higher camera position (a LensCoat rain cover protected most of the camera and lens). An unexpected wind complication was that bobbing with the ducks while looking into the viewfinder contributed to a strong sense of motion sickness.
Ducks floating on water may seem a low challenge to photograph (the proverbial sitting duck), but this scenario was the completel opposite. Many near-1' (0.3m) waves rocking the already-twitchy, constantly-erratically moving ducks and me (at different frequencies) made keeping a duck in the 600mm frame (I started at 840mm with a 1.4x teleconverter) extremely challenging (especially when the duck was obscured by a wave). I monitored image sharpness until becoming confident that a 1/3200 shutter speed eliminated motion blur in most pictures.
One of the biggest wildlife (and portrait) photography challenges is to keep the proper AF point selected. A motionless subject permits a focus and recompose strategy, but moving subjects require selecting a specific AF point that produces the optimal composition while remaining on the subject's eye. Fast AF point selection is an especially big challenge for unpredictable wildlife. Tracking a twitchy, bobbing duck with a specific focus point held on the eye would have been nearly impossible. However, the 600mm, f/4, close distance combination's shallow depth of field made focusing precisely on the eye a requirement.
Eye AF eliminates this challenge for a significant percentage of subjects. With the Sony Alpha a1's eye AF enabled, bird selected as the subject, and the entire AF area chosen (most of the frame), I was left to concentrate primarily on framing the scene and timing the shutter release press. Note that, when eye AF is locking on the subject, gloves are no longer an impediment to cold-weather wildlife pursuits.
When many changes are happening simultaneously, a fast frame rate has your back. I began shooting in the 30 fps drive mode but backed off to 20 fps when I saw how fast the image count was increasing.
Twenty fps is still an exceptionally fast frame rate. Most 20 fps shot sequences captured, minimally, a properly-framed duck image, and often, many well-framed shots, despite all of the motion (ducks would sometimes bob from one frame border to another during a short burst). With 20 fps capture, I didn't feel the need to repair closed necessitating membranes as the previous or next image still had the ideal pose. The foreground and background matter, and wave and reflection nuances vary constantly. These elements can be the deciding factor for selection, and the 20 and 30 fps capture rate provides considerable options in this regard.
That the a1's viewfinder responded fast enough to keep the birds in the frame was remarkable, and the lack of viewfinder blackout was also critical. Even more remarkable was the extremely-high in-focus rate the a1 delivered. In this 3:45 shoot, 8,985 images were captured, and in almost all of them, the eye was in sharp focus – even when the eye bounced into the periphery of the frame.
When packing, four batteries seemed a lot, but 4% of the fourth battery was consumed by the time I walked out of the water. That said, capturing nearly 3,000 images per relatively-small battery is great performance.
Similarly, taking a full terabyte of memory cards seemed overkill, but the last 256GB card was half-filled when shade reached the water. As much as I want to purchase CFexpress Type A memory cards for the a1, I can't get past the current price. Let's put a Type A number on this day. As I write this, adequate 160GB Type A memory cards to contain this under-4-hour shoot would have cost $2,394.00.
In comparison, four fast Lexar 256GB Professional 1667x V60 UHS-II SDXC Memory Cards currently cost $300.00.
With these Lexar cards, the a1 was writing the buffer to the card most of the time. This writing prevents some camera features from being accessible, though image playback functions during the writing process.
Ultra-high performance AF combined with an extreme frame rate results in a problem, albeit a great problem — too many excellent images yield a long selection process. You may have foreseen this issue: reviewing nearly 9k photos is a massive project, and the phenomenal in-focus rate makes that job far more difficult. It is hard to delete excellent pictures, but the quality bar must be raised (or considerable hard drive storage space acquired). Again, the a1's extreme performance create a problem you want to have.
I didn't mention the a1's 50MP resolution in this post, but the bouncing ducks were often not ideally framed. This camera's high resolution meant that significant resolution remained even after cropping deeply.
The Robus RC-8860 Vantage Carbon Fiber Tripod (great tripod, excellent value) provided the support for this shoot. With the tripod leveled, the two-way pan and tilt of the smooth-functioning Wimberley WH-200-S Sidemount Head ensured that every shot was level (though the wave action diminished this requirement).
The bottom line is that Sony Alpha a1, and especially its AF system, is an outstanding performer, as expected.