1 Introduction

The star clusters ESO 93-SC08 and ESO 452-SC11 were discovered during the ESO/Uppsala B sky survey catalogue confection. ESO 93-SC08 and ESO 452-SC11 were reported to have a size of 1' and 2.5' respectively by Holmberg et al. (1977) and Lauberts et al. (1981). Both were indicated as very obscured, the first as a globular cluster candidate and the latter as a globular cluster.

ESO 93-SC08 is projected on the Galactic disk and ESO 452-SC11 in a bulge-halo transition region. These two southern clusters are poorly populated resembling some Palomar clusters.

ESO 93-SC08 has coordinates B(1950) $\alpha$ = 11$^{\rm h}$ 17$^{\rm m}$34$^{\rm s}$, $\delta = -64^{\rm o}$ 56' 48'' and is also designated as GCL B1117-6456 (IAU notation). The Galactic coordinates are $l = 293.508^{\rm o}$, $b = -4.041^{\rm o}$.

By means of the bright giants method Webbink (1985) estimated a horizontal branch (HB) level of $V_{\rm HB} = 22.0$, which he marked as very uncertain. He also provides a reddening of E(B-V) = 0.79, estimated from the modified cosecant law, and a distance from the Sun of $d_{\odot}$ = 59.5 kpc.

Although poorly populated, the cluster structure is rather compact, and from the core and limiting radii provided by Webbink (1985), a concentration parameter c = 1.85 can be estimated.

No colour-magnitude diagram (CMD) is available for the cluster. Besides, after 20 years of its discovery, it is still not clear whether ESO 93-SC08 is a globular or an open cluster.

ESO 452-SC11 (GCL 1636-2818) has B(1950) $\alpha$ = 16$^{\rm h}$ 36$^{\rm m}$18$^{\rm s}$, $\delta$ = $-28^{\rm o}$ 18' 00'' and is located at $l = 351.912^{\rm o}$, $b = +12.07^{\rm o}$.

The cluster is loose but it has a small core. A concentration parameter of c = 0.95 can be estimated from Webbink's (1985) data.

Based on an unpublished CMD reported by Webbink (1985) an HB level of $V_{\rm HB} = 16.66$ was given, and from the HI column density plus galaxy counts method a reddening of E(B-V) = 0.31, implying a distance from the Sun $d_{\odot}$ = 10.3 kpc. He presents a metallicity estimate of [M/H] = -1.01. Harris's (1996) compilation reported E(B-V) = 0.50, $V_{\rm HB} = 16.66$ and a distance $d_{\odot}$ = 7.3 kpc.

Minniti et al. (1995) provided an infrared CMD in K vs. (J-K), where the HB is probably detected at the limit of the photometry. They pointed out that the locus of the red giant branch (RGB) is consistent with E(B-V) = 0.70, assuming Webbink's (1985) metallicity value.

In the present work the V, I CMDs of these clusters are studied, motivated by the fact that they are underpopulated, and probable southern Palomar-type clusters. Another such example is E3 which shows a depleted lower main sequence (MS) above the photometric observational threshold (McClure et al. 1985; Gratton & Ortolani 1987).

In Sect. 2 the observations are described. In Sects. 3 and 4 we discuss respectively ESO 93-SC08 and ESO 452-SC11. Finally, the concluding remarks are provided in Sect. 5.