CHF 2'380
In stock with supplier
The Gemini Combo combines H-alpha filters Prominence and Chromosphere for instant switching via a side-mounted slider. Enjoy the best of both bandwidth options in a single tool, without hardware swapping or refocusing.
The Gemini Combo allows :
Important: for SCT and Maksutov, a front-mount energy rejection filter (ERF) is mandatory to protect the optical tube and obtain optimum performance.
| Type | Gemini H-alpha Combo filter (Prominence + Chromosphere) |
|---|---|
| Compatibility | SCT, Maksutov, F/15-F/30 refractors |
| Eyepiece outlet | 1.25″ standard, 1.25″ snout included + 2° off-axis adapter for ERF |
| Barlow / Optics | No integrated Barlow - 0 power, filter only. Optional telecentric barrows available. |
| Blocking filter | Integrated, 25 mm |
| Clear aperture | 21 mm |
| Power supply | USB 5 V 1.5 A, incl. 90-240 V mains adapter |
| Tuning | Wheels for wing shift ±0.5 Å with notches every 0.1 Å; LED status: power, warming, ready, fault |
| Warranty | 5 years |
| Supplied box | Hard case for protection and transport |
| Observation | Full disk up to ~1800 mm focal length; no aperture limitation, use with SCT and Maks off-axis ERF |
| Optional accessories | 8h battery pack |
| Criteria | Prominence | Chromosphere |
|---|---|---|
| Bandwidth FWHM | Wider (>0.6 Å) - brighter | Narrower (<0.5 Å) - better surface contrast |
| Filaments | Difficult to observe | Visible and detailed |
| Protuberances | Very shiny blade | Visible but less brilliant |
| Contrast | Less contrast, brightness priority | High contrast, ideal for chromospheric detail |
| Recommended use | Quick visual observation | Detailed observation and astrophotography |
