Comparison between UBV- and RGU-photometrically determined space density functions in a starfield close to the galactic centre (SA 133)

Two different photometric methods, RGU and UBV, were applied to data from three high-latitude stellar fields to obtain space density functions of the individual star types to investigate the analytical-system independence of the observations. The results were sufficiently similar to encourage a second survey of a low-latitude star field (SA 133) within 10 deg of the galactic center for further comparisons. The main point of the investigation was to evaluate if interstellar extinction effects and the large proportion of late-type giants in the low latitude region limit the usefulness of either of the two techniques for identifying stellar types. Fractioned two-color diagrams proved to be effective for controlling contamination from the reddening caused by interstellar dust in observations of disk, halo and giant stars. Analyses of the data from both systems indicates a star-type identification error rate of 6.5 percent, about what is available with other fields.