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BV CCD photometry of the central (1.5 arcmin x 2.0 arcmin) part of the mildlyconcentrated outer-halo globular cluster NGC 6229 is presented. The datareduction in such a crowded field was based on a wavelet transform analysis.Our larger dataset extends the previous results by Carney et al. (1991, AJ,101, 1699) for the outer and less crowded fields of the cluster, and confirmsthat NGC 6229 has a peculiar color-magnitude diagram for its position in theGalaxy. In particular, NGC 6229's horizontal branch (HB) presents severalinteresting features, among which stand out: a well populated and very extendedblue tail; a rather blue overall morphology, with (B-R)/(B+V+R) = 0.24+/-0.02;a bimodal color distribution, resembling those found for NGC 1851 and NGC 2808;and gaps on the blue HB. NGC 6229 is the first bimodal-HB cluster to beidentified in the Galactic outer halo. A low value of the R parameter isconfirmed, suggestive of a low helium abundance or of the presence of a quitesubstantial population of extreme HB stars fainter than our photometric limit(~ 2.5 mag below the RR Lyrae level in V). Twelve new possible variable starswere found in the central part of the cluster. The morphology of the red giantbranch (RGB) also seems to be peculiar. In particular, the RGB luminosityfunction ``bump'' is not a prominent feature and has only been tentativelyidentified, on the basis of a comparison with a previously reported detectionfor M3 (NGC 5272). Finally, we compare the properties of NGC 6229 with thosefor other outer-halo globular clusters, and call attention to what appears tobe a bimodal HB distribution for the outer-halo cluster population, whereobjects with very red or very blue HB types are much more frequently found thanclusters with intermediate HB types.Comment: 31 pages, LaTeX, uses AASTeX v4.0, 11 postscript figures and 7  postscript tables pasted into text. To appear in The Astronomical Journal  (Feb. 1997 issue

Stellar Photometry of the Globular Cluster NGC 6229.I.Data Reduction and Morphology of the Brighter Part of the CMD