The systematic deformations are usually accommodated by
adding a function f(x,y) of the image coordinate to the
projective relations.
xp" = Px" (Np,Ep,Hp) + Ex? (Xp, vp(9)
yp" = Py" (Np,Eo,Hp) + Fy“ (Xp, vp) (1)
For block adjustment, F is approximated by polynomials in
x and y with a limited number of unknown coefficients.
This approach, although valid, poses a large number of
practical problems, such as: which polynomial to choose,
how to separate systematic deformations from blunders,
which ground control distribution is necessary for
avoiding under-determination etc. (see also Kubik, 1988).
We therefore propose here a novel and elegant approach to
this problem, which also is valid for other projections
such as existing in remote sensing, tomography and other
fields.
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