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MIPSGAL is a 278 deg2survey of the inner Galactic plane using the Multiband Infrared Photometer for Spitzeraboard the Spitzer Space Telescope. The survey field was imaged in two passbands, 24 and 70 ?m with resolutions of 6? and 18?, respectively. The survey was designed to provide a uniform, well-calibrated and well-characterized data set for general inquiry of the inner Galactic plane and as a longer-wavelength complement to the shorter-wavelength Spitzersurvey of the Galactic plane: Galactic Plane Infrared Mapping Survey Extraordinaire. The primary science drivers of the current survey are to identify all high-mass (M> 5 M?) protostars in the inner Galactic disk and to probe the distribution, energetics, and properties of interstellar dust in the Galactic disk. The observations were planned to minimize data artifacts due to image latents at 24 ?m and to provide full coverage at 70 ?m. Observations at ecliptic latitudes within 15° of the ecliptic plane were taken at multiple epochs to help reject asteroids. The data for the survey were collected in three epochs, 2005 September-October, 2006 April, and 2006 October with all of the data available to the public. The estimated point-source sensitivities of the survey are 2 and 75 mJy (3 ?) at 24 and 70 ?m, respectively. Additional data processing was needed to mitigate image artifacts due to bright sources at 24 ?m and detector responsivity variations at 70 ?m due to the large dynamic range of the Galactic plane. Enhanced data products including artifact-mitigated mosaics and point-source catalogs are being produced with the 24 ?m mosaics already publicly available from the NASA/IPAC Infrared Science Archive. Some preliminary results using the enhanced data products are described.

We describe improvements to the data processing pipeline for the SpitzerMIPSGAL survey of the Galactic plane. These involve both improvements to the processing of the 24 ?m data, in particular the handling of saturations and near-saturated data, and mitigation of various artifacts not corrected in the basic calibration pipeline. The artifacts addressed postpipeline are typically caused by passage across bright point sources very common in the Galactic plane, and include column-to-column "jailbar" striping, latency effects resulting in both short-duration afterimages and long-duration responsivity depressions, scattered light, and background-level mismatches. We describe the artifacts phenomenologically and present in detail the algorithms developed to correct them.