| Queensgate FPI | ICOS FPI | p260 | p501 | p751 |
| Order (in H-alpha line) | 235 | 501 | 751 |
| Interfringe (in H-alpha) | 28 A (1270 km/s) | 13 A (600 km/s) | 8.7 A (390 km/s) |
| Spectral range | 5000-7000 A | 5000-8000 A | 4500-9000 A |
| Finesse (in H-alpha) | 13 | 16 | 20 |
| Sp. resolution (in H-alpha) | 2.1A | 0.8A | 0.4A |
| Number of spectral channels | 24-32 | 36 | 40 |
