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We present wide-field near-infrared J and Ks images of the Andromeda Galaxytaken with WIRCam on the Canada-France-Hawaii Telescope (CFHT) as part of theAndromeda Optical and Infrared Disk Survey (ANDROIDS). This data set allowssimultaneous observations of resolved stars and NIR surface brightness acrossM31's entire bulge and disk (within R=22 kpc). The primary concern of this workis the development of NIR observation and reduction methods to recover auniform surface brightness map across the 3x1 degree disk of M31. Thisnecessitates sky-target nodding across 27 WIRCam fields. Two sky-target noddingstrategies were tested, and we find that strictly minimizing sky samplinglatency does not maximize sky subtraction accuracy, which is at best 2% of thesky level. The mean surface brightness difference between blocks in our mosaiccan be reduced from 1% to 0.1% of the sky brightness by introducing scalar skyoffsets to each image. The true surface brightness of M31 can be known towithin a statistical zeropoint of 0.15% of the sky level (0.2 mag arcsec sq.uncertainty at R=15 kpc). Surface brightness stability across individual WIRCamframes is limited by both WIRCam flat field evolution and residual skybackground shapes. To overcome flat field variability of order 1% over 30minutes, we find that WIRCam data should be calibrated with real-time skyflats. Due either to atmospheric or instrumental variations, the individualWIRCam frames have typical residual shapes with amplitudes of 0.2% of the skyafter real-time flat fielding and median sky subtraction. We present our WIRCamreduction pipeline and performance analysis here as a template for futurenear-infrared observers needing wide-area surface brightness maps withsky-target nodding, and give specific recommendations for improving photometryof all CFHT/WIRCam programs. (Abridged)

Andromeda Optical and Infrared Disk Survey I. New Insights in Wide-Field Near-IR Surface Photometry