The Panasonic G9 uses a Contrast Detect AF system and the company's Depth from Defocus (DFD) technology. DFD has consistently resulted in the best AF performance of any CDAF system we've tested. And with the G9, Panasonic's improved DFD further by increasing the processing speeds used to calculate subject distance. That's a good thing, because the G9 can now shoot bursts as fast as 20 fps with AF. And like the GH5, the G9 offers 225 selectable points.

AF custom settings

The Panasonic G9 also features the same AF Custom settings as the Panasonic GH5. For the sake of our AF testing we left the camera in its default 'Set 1' custom setting (spoiler: with excellent results).

Continuous AF

It's worth mentioning before we dive into our first autofocus demonstration that the very nature of how Contrast Detect works is by very rapidly 'wobbling' the focus element back and forth to constantly ensure peak sharpness. This means that peppered throughout your bursts, you will inevitably have images that aren't quite tack-sharp, but aren't unusably soft. For anything but critical usage though, the results should be acceptable.

In our first demonstration, we see how fast the Panasonic G9 can assess depth and refocus on a subject well-separated from the background, moving toward the camera. This test was done using a single point at 20 fps.

The results are very positive: The G9 essentially aces this scenario, with almost all images tack sharp or acceptably sharp. We also ran this same test using the 9 fps mode and had equally impressive results.

Subject tracking

In our next text we examine how the G9 handles a subject moving toward the camera in an irregular pattern. For this test we turn to the camera's 'Tracking AF' mode which attempts to recognize and follow a subject, whose movement is somewhat unpredictable.

Again, the results of this test are really quite impressive, with the vast majority of frames in focus and the camera easily able to stay on our subject for the majority of the runs we shot (Note: the above roll-over shows every other frame to better demonstrate the camera following our subject from one side of the frame to the other).

Again, our experience subject tracking in 9 fps was similar, with most of the photos sharp or acceptably sharp.

Close-range AF

Next up, our close-range AF test. This simulates photographing friends or family in a dimly lit social situation. For this test we tried both the 'Face Detect' AF mode as well as the 'Tracking AF' mode using Single Drive in AF-C. Ultimately, Face Detect proved more effective, though both provided solid hit rates.

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One thing worth pointing out if you watch the video, it is VERY hard to tell when you got a shot in focus or not when shooting with this camera. Still, if you pop into the gallery you'll see that nearly 90% of images are tack sharp or reasonably sharp when using Face Detect, impressive.

With such good results, we decided to up the challenge and try both Face Detect and Subject Tracking on our dimly-lit subjects, while firing a burst at 20 fps. Under these circumstances we actually found subject tracking to give a slightly better hit rate than face detect. The results of the 50 frame burst are in the gallery below:

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Honestly, a surprising number of images from this burst are in focus images. It's also interesting to note that while you can tell the camera struggles to keep up with some of the sudden movement, it eventually does, and at no point does the G9 seem to lose our subject.

Final thoughts on AF

The Panasonic G9 represents the most capable Contrast Detect AF camera ever released. Proof of this is the fact that is aced all of our autofocus tests; for a look at how the AF performed during a college basketball game, read our G9 shooting experience.

Image Stabilization

The Panasonic G9 offers the latest version of Dual I.S. 2, which combines 5-axis sensor stabilization with lens-based stabilization (using compatible glass). According to press materials, the G9 is CIPA-rated at 6.5-stops when using only the in-body stabilizer with shorter lenses, and maintains that rating at telephoto when combined with a stabilized lens.

We ran it through our standard IS test which historically tends to result in figures slightly lower than the CIPA rating. At 200mm using Dual I.S. 2 the G9 provided 5 2/3 stops advantage over hand-held shooting, making it the most effective IS system in any camera we’ve tested to date. Even down at 1/5 sec we were finding the majority of image acceptably sharp with IS on. By comparison the Olympus OM-D E-M1 II provided 5-stops at 200mm in our IS test.

At 24mm, the difference is less notable, but the G9 still offered a 3-stop advantage with IS on. By comparison the EM-1 II gave 2.5-stops at 24mm.