J − H versus H − K color−color versus J brightness diagram. The solid gray lines represent the main sequence and giant sequences from Bessell & Brett (1988). The dashed gray line represents the main sequence from Kraus & Hillenbrand (2007). The sizes of the symbols are proportional to the J-band brightness. Sources taken as foreground candidates are marked in blue, while rejected sources, mostly extincted sources, are marked in red.