Sony has announced that its a7 II will receive a firmware update that
will boost its autofocus performance with adapted lenses as well as add
support for uncompressed Raw. Previously, the a7 II only used contrast
detect AF with lenses adapted via passive adapters. That meant a lot of
hunting, and unusable continuous AF.
Phase-detect AF with adapted lenses
The update enables the on-sensor phase detection system to work with
adapted lenses. This should, theoretically, allow it to behave much like
the a7R II, which is quick to focus many A-mount and 3rd party lenses,
even able to continuously refocus quickly on approaching or receding
subjects.
You can select phase detection for adapted lenses via a menu option
the update will add. Depending on the option you choose in this menu
item, the camera will use phase detection (for
speed) or contrast detection (for
accuracy, at the cost of
speed)
when using non-native lenses. We should point out that in our limited
tests, on-sensor phase detection even with non-native lenses appears to
exhibit the high
accuracy of contrast detection. Therefore,
enabling PDAF should bring many benefits, with little to no cost. And
despite the a7 II's sensor having far fewer phase detection elements
than the a7R II, and likely lower speed of readout, the company says the
camera will be able to offer some degree of object recognition and
tracking with A-mount lenses, meaning they are also likely to work with
Canon lenses via third-party adapters.
Advanced subject tracking with adapted lenses?
Frankly, though, we don't expect the more advanced subject tracking
modes, like eye AF and Lock-on AF, to function with adapted lenses, as
they do not function on the a7R II. Rather, much like the a7R II, we'd
expect the firmware to enable depth-based subject tracking - or the
ability of the camera to automatically choose AF points to stay on a
moving target using mostly phase information - in the camera's 'Wide' AF
area mode. This is welcome, but if that's the only mode that allows
general subject tracking with adapted lens, it won't suit many
photographers, since 'Wide' never allows one to even specify what your
subject is (the camera always chooses one for you). These, and other
limitations like 3fps max drive for continuous AF, are real, and limit
your ability to shoot sports in fast-paced, reliable manner. Face
detection AF in continuous, though, works remarkable well, and with the
phase detection support this update brings, makes for a usable way to
ensure the primary face in your scene is in focus at the time of
capture.
Uncompressed Raw
In addition, the firmware update will add the uncompressed Raw option
Sony introduced in the a7R II and available in the a7S II. Uncompressed
Raw avoids the compression artifacts we, and many others, found could
be introduced by Sony's compression algorithms.
Ideally, we hear you: a lossless compressed option would be nice, but
this is a start, and it is encouraging to see previous cameras updated
with an uncompressed Raw that avoids all potentially image degrading
steps in the Raw file writing process. The update will also allow the
movie record function to be assigned to a wider range of buttons. The
update will be available around November 17th.
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