Pegasus Astro Oxygen III / O-III Narrowband (7nm) Imaging Filter - 2" Mounted

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OIII-CCD 7nm filter is designed for nebula observation allowing 7nm bandwidth of light centered on a wavelength of 500nm through, which corresponds to OIII emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
- SKU: PEG-FLTR-2M-O3
- Filter Size: 2 inch
- Polish: 1/4 wavefront, Parfocal
- Transmission Range: T > 80% 500 nm, 7nm FWHM
- Coatings: Multilayer Anti-reflection
- Type: Narrowband (7nm)
- Shape: Round
- Thickness: 5mm (filter) + 2.5mm (thread)
- Thread: M48, 0.75 pitch
A note about possible halos in narrowband Pegasus filters: Pegasus has extensively tested their narrowband filters and are very satisfied with the result. However, they have observed additional lenses in the optical path or extremely bright stars in the FOV can cause spikes or halos, not related with filter coatings. If you observe or have any concerns with halos in your Pegasus filters, you will need to work directly with Pegasus to discuss the issue. If Pegasus confirms the issue (after communication and troubleshooting with customers) of a filter defect, they will replace the filter.
Other Information
- Country of Manufacture: China
OIII-CCD 7nm filter is designed for nebula observation allowing 7nm bandwidth of light centered on a wavelength of 500nm through, which corresponds to OIII emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
- SKU: PEG-FLTR-2M-O3
- Filter Size: 2 inch
- Polish: 1/4 wavefront, Parfocal
- Transmission Range: T > 80% 500 nm, 7nm FWHM
- Coatings: Multilayer Anti-reflection
- Type: Narrowband (7nm)
- Shape: Round
- Thickness: 5mm (filter) + 2.5mm (thread)
- Thread: M48, 0.75 pitch
A note about possible halos in narrowband Pegasus filters: Pegasus has extensively tested their narrowband filters and are very satisfied with the result. However, they have observed additional lenses in the optical path or extremely bright stars in the FOV can cause spikes or halos, not related with filter coatings. If you observe or have any concerns with halos in your Pegasus filters, you will need to work directly with Pegasus to discuss the issue. If Pegasus confirms the issue (after communication and troubleshooting with customers) of a filter defect, they will replace the filter.
OIII-CCD 7nm filter is designed for nebula observation allowing 7nm bandwidth of light centered on a wavelength of 500nm through, which corresponds to OIII emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
- SKU: PEG-FLTR-2M-O3
- Filter Size: 2 inch
- Polish: 1/4 wavefront, Parfocal
- Transmission Range: T > 80% 500 nm, 7nm FWHM
- Coatings: Multilayer Anti-reflection
- Type: Narrowband (7nm)
- Shape: Round
- Thickness: 5mm (filter) + 2.5mm (thread)
- Thread: M48, 0.75 pitch
A note about possible halos in narrowband Pegasus filters: Pegasus has extensively tested their narrowband filters and are very satisfied with the result. However, they have observed additional lenses in the optical path or extremely bright stars in the FOV can cause spikes or halos, not related with filter coatings. If you observe or have any concerns with halos in your Pegasus filters, you will need to work directly with Pegasus to discuss the issue. If Pegasus confirms the issue (after communication and troubleshooting with customers) of a filter defect, they will replace the filter.
Other Information
- Country of Manufacture: China
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Pegasus Astro Oxygen III / O-III Narrowband (7nm) Imaging Filter - 2" Mounted


















