Baader O-III Narrowband Filter 6.5nm
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Vai al moduloThe Baader O-III Narrowband Filter 6.5nm is a narrowband filter that passes blue-green light at 500.7nm, the wavelength at which planetary nebulae and supernova remnants rich in doubly ionized oxygen shine. Optimized for modern CMOS cameras.
What it's for
Linear filter with a 6.5nm FWHM passband, recommended for optical systems from f/10 to f/3.5 — the vast majority of amateur telescopes in use. It reveals the details of planetary nebulae and supernova remnants even under light-polluted skies, since the narrow passband effectively blocks skyglow and artificial lighting.
Baader CMOS-Optimized technology
The 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. The filter is individually polished and coated, with no exposed coating edges.
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 |
|---|---|
| Type | O-III Narrowband |
| Central wavelength | 500.7 nm |
| Bandwidth (FWHM) | 6.5 nm |
| Recommended optical systems | f/10 to f/3.5 |
| Filter thickness | 2 mm |
| Coating | Reflex-Blocker™, Life-Coat™ |
| Brand | Baader Planetarium |
Who it's for
Ideal for astrophotographers who want to purchase the individual filters of the SHO palette separately (for example to complete or replace an existing set), or for those who photograph exclusively planetary nebulae and supernova remnants in O-III without needing H-alpha or S-II. Compatible with filter wheels and most mono CMOS cameras.