... 32, No. 8, pp. 592­603. i Central Regions of the Early-Type Galaxies in the NGC 3169 Group O. K. Sil'chenko1* and V. L. Afanasiev 1 2 Sternberg Astronomical Institute, Universitetskii pr. ... The mean age of the stellar populations in the centers of all three galaxies has been found to be approximately the same, 1 Gyr. ... In contrast, in NGC 3166, there is a metallicity gradient, but the stellar age remains approximately constant up to a distance of 8 from the center. ...

... The instrument uses a high-speed optical system to form an image on the entrance slit of a matching stigmatic spectrograph, which then disperses a spectrum of a strip of the sky onto a charge-coupled device (CCD). ... Fast camera lenses, narrowband Ha пlters, and charge-coupled device (CCD) detectors combine to give an image пeld of several degrees with 0Ў resolution and a .1 sensitivity to 1 R or less (Gaustad et al. ... The spectrum and the sky are imaged on the CCD detector. ...