SII 6nm CCD MaxFR - 1.25" (M28.5)
Astronomik
From $199.95
4 stores
The Astronomik SII 6nm CCD MaxFR is a narrowband emission-line filter designed specifically for high-quality CCD astrophotography imaging of sulfur-ionized (SII) nebulae and supernova remnants. With a 6nm bandwidth isolating the 671.7nm and 673.0nm SII emission lines, this filter provides guaranteed transmission of over 90% and excels at enhancing contrast in both light-polluted and dark-sky environments. The MaxFR coating enables use across fast optical systems from f/2.2 to f/8, making it ideal for rapid astrographs like RASA and Epsilon telescopes while maintaining diffraction-limited optical performance.
High Point Scientific
Astronomik SII 6 nm CCD Filter - 1.25"
Ships to US only
$199.95
OPT
SII 6nm CCD MaxFR - 1.25" (M28.5)
Worldwide shipping
$259.95
Agena Astro
Astronomik Sulfur-II / S-II MaxFR 6nm High-Speed Imaging Filter - 1.25" Mounted
Worldwide shipping
$269.95
Astroshop.eu
Filters SII 6nm CCD MaxFR 1,25"
Worldwide shipping
€269.00
~$319.34
Specifications
| Coating Type | MaxFR |
| Usable Focal Ratio Range | f/2.2 to f/8 |
| Filter Mount Size | 1.25 in |
| Diffraction Limited | ✓ |
| Glass Thickness | 1 mm |
| Filter Type | Narrowband Emission-Line (SII) |
| Thread Type | M28.5 |
| Central Wavelength | 671.7 |
| Bandwidth | 6 |
| Warranty | 10 |
| Blocking Range | UV to IR |
| Typical Transmission | 93% |
| Parfocal | ✓ |