OIII 6nm CCD MaxFR Filter - 2" (M48)
Astronomik
From $639.95
3 stores
In stock
The Astronomik OIII 6nm CCD MaxFR Filter is a premium narrowband imaging filter optimized for fast optical systems used in deep-sky astrophotography. With a 6nm full-width half-maximum bandwidth, it isolates oxygen-III emission lines at 496nm and 501nm to provide exceptional contrast when imaging planetary nebulae and oxygen-rich emission nebulae. The MaxFR coating enables unlimited usability from f/2.2 to f/8, making it ideal for imaging with fast astrographs like the Celestron RASA and Takahashi Epsilon series while maintaining high transmission and excellent out-of-band blocking from UV to infrared.
Specifications
| Guaranteed Transmission at OIII | 88% |
| Transmission at f/2 | 90% |
| Filter Type | Narrowband Emission Line |
| Central Wavelength | 501 |
| Filter Mount | 2 in |
| Maximum Focal Ratio Support | f/8 |
| Coating Type | MaxFR |
| Bandwidth (FWHM) | 6 |
| Glass Thickness | 1 mm |
| Diffraction Limited | ✓ |
| Minimum Focal Ratio Support | f/2.2 |
| Parfocal Design | ✓ |
| Typical Transmission at OIII | 92% |