The JHK colour–colour diagram of the 13.5′  ×  13.5′ field surrounding IRAS 07422. The curved lines show the loci of main sequence (continuous, green) and giant (short-dashed, green) stars from Tokunaga (2000). The long-dashed green line shows the loci of CTTS from Meyer et al. (1997). The dotted arrows (red) show the reddening vectors for A_V  ≤  50 derived from the interstellar extinction law given by Rieke & Lebofsky (1985). The black dots show objects with photometric error less than 0.207 mag, which is our 1-σ error for a source of 19 mag in K. Sources which are fainter than 19 mag in K are not shown here. Objects with upper limit magnitudes in J are shows with an upward directed arrow; source #1 with H magnitude also is treated as an upper limit is shown with upward and rightward directed arrows.