Baader f/3 Ultra-Highspeed Filter Set 3.5/4nm (H-alpha/O-III/S-II)
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Vai al moduloThe Baader f/3 Ultra-Highspeed Filter Set 3.5/4nm (H-alpha / O-III / S-II) is the version of the CMOS-Optimized range designed for fast astrographs (though not as extreme as f/2 systems) from f/3.4 to f/2.3, with an ultra-narrow passband for maximum available contrast.
Ultra-narrow passband for fast optics
The set includes an H-alpha filter, an O-III filter and an S-II filter, with a 3.5/4nm FWHM passband, optimised for optical systems from f/3.4 to f/2.3. This configuration offers the maximum possible contrast for high-contrast imaging of emission nebulae, revealing the finest details even under heavy light pollution.
Baader CMOS-Optimized technology
Each filter is coated with Reflex-Blocker™ treatment, which eliminates unwanted reflections even in the presence of auxiliary optics, and with Life-Coat™ technology: a hardened coating that does not flake, does not degrade and lasts the filter's entire lifetime even under the most extreme conditions. The edges are blackened all around, with a visual indicator on the front side for correct orientation during mounting.
Available formats
Available in 7 formats: 1¼" (31.8mm), 2" (50.8mm), 31mm, 36mm, 50.4mm, 50×50mm and 65×65mm.
Technical specifications
| Parameter | Value |
|---|---|
| Filters included | H-alpha, O-III, S-II |
| Bandwidth (FWHM) | 3.5 / 4 nm |
| Recommended optical systems | f/3.4 to f/2.3 |
| Filter thickness | 2 mm |
| Coating | Reflex-Blocker™, Life-Coat™ |
| Brand | Baader Planetarium |
Who it's for
Ideal for astrophotographers using fast astrographs with a focal ratio between f/2.3 and f/3.4 who want the maximum available contrast for imaging emission nebulae, planetary nebulae and supernova remnants in "Hubble Palette" style (SHO), even under light-polluted skies.