Optolong L-Ultimate 2" Dual Narrowband Filter
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Vai al moduloOptolong L-Ultimate 2” – 3nm Dual Narrowband Filter for Astrophotography
The Optolong L-Ultimate 2” is a 3nm dual narrowband filter, the evolution of the well-known L-eXtreme. It precisely isolates the emission lines H-Alpha (656nm) and OIII (500nm) with peak transmission up to 93% and maximum light pollution suppression.
The 3nm bandwidth makes the L-Ultimate ideal for astrophotographers in urban and suburban areas using color CMOS cameras – enabling sessions even under full moon and Bortle 7–9 skies without a complex mono setup.
Key Advantages
- 3nm bandwidth: maximum suppression of artificial light sources
- Peak transmission up to 93%
- Works under full moon and heavily polluted skies
- One-filter solution for color CMOS cameras
Technical Specifications
| Filter type | Dual Narrowband (H-Alpha + OIII) |
| Bandwidth | 3nm |
| Peak transmission | Up to 93% |
| Format | 2” (50.8mm) |
| Substrate | Schott glass |
| Thickness | 2.0mm |
| Surface quality | 60/40 (MIL-O-13830) |
| Parallelism | <30" |
| Flatness | 1/4λ |
| Recommended camera | Color CMOS |