Antlia SII Filter 3.5nm 36mm – Ultra Narrowband Astrophotography
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Vai al moduloAntlia SII Filter 3.5nm 36mm – Ultra Narrowband for Astrophotography
The Antlia SII 3.5nm 36mm is a 3.5nm ultra narrowband filter on SII at 671.6nm. Transmission >88% and OD3 blocking from 300–1100nm. Schott monolithic substrate, parafocal ±0.05mm, hand-blackened edges. Compatible with telescopes up to f/2.0. SII component of the SHO set for Hubble Palette with mono cameras.
Technical Specifications
| Filter type | Ultra narrowband SII |
| Central wavelength | 671.6nm |
| Bandwidth (FWHM) | 3.5nm |
| SII transmission | >88% |
| Off-band blocking | OD3 (0.1%) @ 300–1100nm |
| Format | 36mm (unmounted) |
| Substrate | Schott, 2mm ±0.05mm |
| Surface quality | 60/40 (MIL-O-13830) |
| Flatness | 1/4λ |
| Parallelism | 30" |
| Focal ratio | Up to f/2.0 |
| Recommended cameras | CCD/CMOS mono, SHO imaging |