Calibration constant: 0.381E-18 ergs/s/cm^2/counts
Pixel scale: 0.488" for the ungeometrically corrected image.
             1.134" for the image geometrically corrected to match the V-band image.

The Halpha calibration constant includes corrections for atmospheric extinction 
due to the airmass of the observations, the shift in the bandpass due to the 
temperature of the filter, and a contribution from [NII].