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We report results of a program to determine the brightness of the night sky at Kitt Peak during the recent solar minimum. Well-calibrated photometry in B and V suggests that the average brightness of the night sky during this period was approximately V = 21.9, B = 23.0 in magnitudes per square arc second but that variations of a few tenths of a magnitude can occur from night to night, or even during a single night. Since 1987 the sky has already brightened considerably, probably due to the increase in solar activity as the Sun moves toward sunspot maximum in 1991.

We have derived the spatial distribution of the electron temperature and density and the ionic abundances of 0 + , 0 + + , N + , and S + from CCD images of the planetary nebulae NGC 40 and NGC 6826 taken in the important emission lines of [O II], [O III], Hß, [N il], and [S il]. Spectra constructed at several positions across these nebulae through a simulated aperture corresponding to that used for classical spectroscopy agree very well with previous observations. Advantages of the imaging technique include complete spatial coverage and excellent spatial resolution, good light throughput, reduced effects of spatial averaging over filamented and knotted regions, elimination of the effects of atmospheric dispersion, and absolute spectrophotometry for objects having angular sizes of several arc min.The disadvantages include additional effort to analyze the data, limited spectral coverage, and added difficulties in deblending nearby lines, removing the nebular continuum contribution, and correcting for nonphotometric conditions.

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