This workflow join 13 votables, obtained from the workflow "Extract SDSS field information and PSF" in order to get a only one votable with all the information. Also it adds the columns "zp", "magzeropoint", xconvsize, yconvsize that are calculated from values provided in the inputs. The zp is -( aa + kk * airmass ), the magzeropoint is zp + 2.5 * log10(53.907456), the xconvsize is roundUp(nx/10) and the yconvsize is roundUp(ny/10)