The camera response curve is simplified using the EMoR sensor model which reduces the variation to five numbers, these are the Ra, Rb, Rc, Rd & Re image (i) parameters (the default values of 0.0 are equivalent to an 'average' generic sensor).
The vignetting model is represented by a polynomial with four parameters: Va (this is always 1.0 and doesn't need to be optimised) and Vb, Vc & Vd (which default to 0.0 - equivalent to no vignetting). The vignetting centre can also be different from the geometrical centre, this is specified by Vx & Vy (both default to 0.0).
Exposure (EV) is represented by a single value Ev (defaults 0.0, equivalent to no-change).
The white balance is represented by multipliers for the red and blue channels Er and Eb (the defaults of 1.0 are equivalent to no-change).
A typical 'v' variable line configuration would look like this, i.e. optimise camera response curve and vignetting for image 0 and exposure for images 1, 2, 3 and 4:
v Ra0 Rb0 Rc0 Rd0 Re0 Vb0 Vc0 Vd0 v Ev1 Ev2 Ev3 Ev4
(vignetting centre and white balance are left unchanged)
Expert and debugging options:
This man page was written by Cyril Brulebois <cyril.brulebois@enst-bretagne.fr> and is licensed under the same terms as the hugin package itself.