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Photogrammetric observation of the variation of intrinsic
parameters for zoom lenses
Bahadir Ergun
Department of
Geodesy and Photogrammetry, Gebze Institute of
Technology, 41400 Cayirova, Gebze, Kocaeli, Turkey. E-mail:
bergun@gyte.edu.tr.
Accepted 15 February, 2010 |
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Today, non-metric cameras are
used
wide-spread in
close-range photogrammetric applications. Such professional
cameras can be combined with both digital and mechanical
zooming satisfactorily. Optical behavior of the lenses is
changed depending on the feature of the optical system used
during the zooming process. This so-called change is
arranged by optimizing the number of pixels used on the
digital sensor, on the projection plane. The problem of high
definition, digital, non-metric professional cameras is that
while sharpening the image, it deteriorates the definition
of the image plane. Industrial cameras, which are used in
industrial production, can overcome this problem by using
additional image enhancement instruments. These digital
non-metric cameras, which are generally used in close-range
photogrammetry and in architectural photogrammetry, are
calibrated by fixing for maximum and minimum zooming focal
length and they are suitable to be used in this range. In
this study, an Olympus E10 camera is calibrated to meet the
need for the modification, for different focal lengths. Its
calibration data, which is obtained in 3D test field,
together with the distortions on the object, is used to
detect the optical behavior of zooming object for mechanic
zooming.
Key words:
Camera calibration, zoom lens distortion, close range
photogrammetry, parameter estimation, parameter analysis. |
