A demonstration of the "Left Autofocus" issue, which afflicts an unknown
percentage of D800/D800E bodies. In this issue, a photo focused with
the leftmost autofocus point is out-of-focus, whereas photos taken with
the center or rightmost autofocus points are in-focus.
The problem
occurs most often with wide-angle, wide-aperture lenses, such as the
24mm f/1/4, the 14-24mm f/2.8, and the 28mm f/1.8. For my demonstration I
used the 24mm f/1.4, which seems to be most affected out of the three
lenses. I describe the process/methodology I used to test for the issue
and then demonstrate the issue in practice with a live autofocus
session. You can read more about this on my blog at: http://testcams.com/blog/2012/06/20/nikon-d800-left-autofocus-point-issue
Solving AF Problems - 8 Common Autofocus Problems - And Their Solutions
I was so busy zooming in on the right and left focus points, I passed
right by the center focus point photos. I mean, who would have thought
that in order to “fix” my D800 left side autofocus issues, Nikon’s
technicians would simply ruin the focus of the camera’s best sensor
point – the center? No one would do that…would they?
That’s when
reality hit. The left and right focus points looked good, but the center
– terribly out of focus. Not one of the 15 pictures taken with
autofocus using the center point was remotely close to the sharpness of
the Live View shots, which were all perfect. I went back and attempted
to dial in some autofocus fine tuning adjustments based on taking a few
shots of my LensAlign system, but had to use numbers ranging from +15 to
+20 to get the center focus point in sharp focus. And even then some
lenses were still showing some bias toward front focusing that I could
not compensate for. Naturally when I then shot my test target again
with the left autofocus point, the image was blurrier than a Joan Rivers
glamor photo! Sigh…
