| aperture of instrument | 7 X 50 mm binoculars | 7.5 cm (3 in) telescope | 10 cm (4 in) telescope | 15 cm (6 in) telescope | 20 cm (8 in) telescope | 30 cm (12 in) telescope |
| closest separable stars (sec) | 4".56 | 1".28 | 1".52 | 0".76 | 0".57 | 0"38 |
| approximate magnitude limite | 9.0 | 11.4 | 12.0 | 12.9 | 13.5 | 14.4 |