Appendix A of McComas et al.  documents important details of the TWINS data processing, including improved procedures for binning, smoothing images to a given level of statistical accuracy, and differential background subtraction. Please use this paper/appendix as the citable reference for this processing of the TWINS data.
Reference: McComas, D. J., N. Buzulukova, M.G. Connors, M.A. Dayeh, J. Goldstein, H.O. Funsten, S. Fuselier, N.A. Schwadron, and P. Valek, Two Wide-Angle Imaging Neutral-Atom Spectrometers and Interstellar Boundary Explorer energetic neutral atom imaging of the 5 April 2010 substorm, J. Geophys. Res., 117, A03225, doi:10.1029/2011JA017273, 2012.