stecf.impol - Features

• All the instrumental set-up, such as filters, polarizers, rotation angles, etc. are read from the image headers.
• Many input images ( 3 < N < 64) can be processed.
• HST instruments FOC , NICMOS and WFPC2 are handled; ACS will be added in the near future.
• Data from non-HST instruments with polarization analyzers can be added by including a table file listing the instrument polarization properties.
• Output images can be rebinned to increase the polarization signal-to-noise per output pixel.
• Polarization vector maps can be flexibly plotted with user choice of vector size, density of vectors and range of plotted magnitudes. Maps can be overplotted on images using standard IRAF facilities.
• Output error images have fully propagated statistical errors from the input error images. The bias on the polarization values for large fractional polarization errors is corrected.