Autodesk 551A1-05B111-1001 - Stitcher Unlimited 2009, Руководство пользователя

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Stitcher TM
User Guide
85
Sensor shift values
The sensor shift value helps to compensate the displacement of the sensor with regard
to the optical center of the lens. In modern digital cameras, the sensor is not usually
exactly centered with the camera axis.
To change the sensor shift values:
1
If you know the exact value for the Sensor Shift select the parameter type Fixed
from the drop-down list. Otherwise, select Initialized .
2
Enter a value in the x and y fields to set the displacement and press the Tab key on
the keyboard.
NOTE The parameters are calculated automatically when the camera is adjusted. The
parameters can change from one panorama to another; the adjustment is specific to each
project.
Distortion values
Lens distortion causes straight lines in images to appear curved. If a picture is taken of
a square that almost fills the film area, the edges of the box are rarely perfectly straight
and the center of each side of the image will bow slightly inward or outward.
Zoom lenses may typically exhibit a positive linear distortion at their shortest focal
length and a negative one at the longest focal length. The default value is set to no
distortion. However, taking distortion into account improves the accuracy of the
camera calibration.
TIP If your images are too distorted, calibrate them first (see “Stitching highly distorted
images” on page 116). In this case, the distortion edit field shows the residual distortion that
calibration failed to correct.