Johnson-Cousins photometry of comparison stars
star#     U 	     B 	          V                Rc 	          Ic
==============================================================================
4    15.49 (0.07) 15.01 (0.06)  14.18 (0.04) 	13.74 (0.04) 	13.28 (0.04)
10   15.00 (0.05) 15.01 (0.05)  14.60 (0.05) 	14.34 (0.05) 	14.03 (0.05)
11   15.39 (0.07) 15.47 (0.07) 	14.94 (0.04) 	14.65 (0.05) 	14.32 (0.05)
C1 	  	        	15.88 (0.07) 	15.50 (0.07) 	15.08 (0.07)
C2 	  	  	        16.12 (0.08) 	15.66 (0.08) 	15.21 (0.08)
===============================================================================

V,Rc,Ic were taken from Fiorucci & Tosti (A&ASuppl. 116, 403, 1996)
U,B data from Smith et al. AJ 90, 1184, 1985)