jayphotoworks said:
If you refer to the A7III review on Dpreview, you can see within the same type of tests, the A7III outperforms the 6DII on all fronts including autofocus tracking (even with the 6DII's DPAF). Then it goes on to be better at DR, AF coverage, burst shooting and oversampled 4K. If none of those items are important, than what is? Is it biased? Should I write a review and say, well the 6DII is better because it has an articulating screen, and Canon has more market share? The reader can make their own choices, but the A7III is better than the 6DII at those things that are kind of "important" for cameras right?
The A7M3 has much better autofocus TRACKING of certain subjects like human faces. There are some cool features like face registration and face preference, and of course, Eye AF is great for human subjects in well-lit conditions. But it is TERRIBLE in comparison to the 6DII in:
- Raw autofocus speed in good conditions
- Raw autofocus speed in dimly lit conditions
- Autofocus in very poor lighting where an AF illuminator is needed -- is excellent in 6DII and unusable in Sony
- Accuracy of spot selection in PDAF mode (the Sony is good for choosing the right point in accurate focus-magnified Autofocus in Contrast Detect mode, but then it's painfully slow)
- Continuous autofocus of a small subject by manually tracking it (such as a bird)
- Autofocus hunting in non-continuous AF modes
- Autofocus at smaller apertures (where the Sony uses crappy, stopped down autofocusing)
To me, every cool feature in the A7M3 is dwarfed by relatively poor autofocus. 20 steps of DR does nothing for me if my bird is blurry.
All things being equal (composition, quality of lenses, lighting, etc.), a camera needs 2 things to get a good picture: good focus, and good exposure. I can figure out the exposure part, by a combination of AE and experience. But I rely on the camera for good focus, and the Sony is not up to snuff when the conditions are challenging.
By the way: subject tracking is much better on the 6DII in DPAF (live view) mode than in PDAF. That said, as a stills photographer, this really isn't a feature that is very important, because usually, I need to keep the focus point on the subject anyways (otherwise, it will be poorly composed). For video, I get it.
Also, Sony has absolutely ridiculous AE ergonomics, where the camera can't link AE to the back button autofocus. So, if you press the back AF button, the camera won't provide AE. You must half-press the shutter to do that (or program it to another, separate button). Similarly, Sony has ridiculous shutter wheel ergonomics. You can't change the shutter speed/aperture when you your finger is on the AF. Often, I will back-button autofocus, and adjust my shutter speed with my index finger between shots. But on the Sony, you need to release AF in order to adjust exposure.