Hybrid Viewfinder And Monitor - FujiFilm X-Pro1 User Manual

The optical viewfinder also has disadvantages: it doesn't
"see" the exact image that the camera does. This is
because it lies on a different optical axis from the lens,
creating a parallax error that all optical viewfinder cameras
exhibit.
Human vision is also based on input from sensors on
two different optical axes: our left and right eyes. This
trait allows us to illustrate the parallax effect with a small
experiment. Hold your pointed index finger at a short
distance from your nose. Now view it alternately with
your left and then your right eye and you will see how
your finger appears to "jump" from one side to the other.
Next, move your finger farther away from your face and
repeat this test. The difference between the appearance
of your finger as seen with your left and right eye should
be much smaller now.
The X-Pro1 also experiences this effect since the
lens and the optical viewfinder are on different optical
axes. This characteristic gives rise to two undesirable
phenomena:
• The white image frame that you see in the optical view-
finder doesn't correspond exactly to the actual image
frame that the camera exposes. In reality, the X-Pro1
exposes a slightly larger area than what appears in
the optical viewfinder's digital rectangular frame. The
camera errs on the side of caution and frames some-
thing like 85 percent of the actual exposure area.
• The measuring field for the autofocus shifts in the
same way that the image frame itself shifts as a result
of parallax error. This creates the possibility that you
target a specific (usually small) object in the OVF, only
to have the camera actually focus beyond the object by
a hair's breadth.
2.2

Hybrid Viewfinder and Monitor

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