Antlia 1.25" & 2" Solar Discover 5Å CaK Assembly

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The Antlia Solar Discover 5Å CaK assembly incorporates a set of light-reducing filters to limit solar heat ingress for safe operation during solar imaging. It is specifically engineered to enhance imaging contrast of plage, light bridges, features prominent in the CaK 393.3nm line as well as sunspots.
The Antlia 5Å Ultra Narrow Bandpass Filter features a clear aperture of 12mm (B1200) and a wavelength centered on the Calcium II K-Line at 393.3nm. With its ultra-narrow full width half maximum (FWHM) of 0.5nm, it enables the capture of details in the Sun's chromosphere.
Installation is similar to the Antlia CaK 3nm Solar Herschel Wedge with the assembly placed between the telescope and camera. The unit is CNC machined from aircraft aluminum and oxidized. The filters are assembled within a fully enclosed tube, preventing stray light from entering the light path.
Important Notes:
- If you do not use a barlow lens, your telescope must have a focal ratio >7.
- Optional 2X, 3X and 5X Antlia barlow lenses are available specifically designed for Solar Discover 5Å CaK ; please order them separately if required. Please refer to the installation diagram.
- Optional adjustable aperture diaphragm is available with Dia 2.0mm-25mm. Antlia specifically designed this accessory for Solar Discover 5Å CaK; please order them separately if required.
- Optional 50mm and 70mm extension tubes are provided by Antlia for better focus. Please order them separately if required.
- When you are using a diagonal mirror, or barlow lens supplied by another manufacturer, the ERF filter must be installed in the correct position for safe operation. Please refer to the installation diagram.
- When you are using a telescope with an aperture >100mm, you need to use additional light reduction solutions, such as ERF filters, solar safety films which lower the telescope aperture for safe operation while using Solar Discover 5Å CaK; If without the extra light reduction solution, the Solar Discover 5Å CaK can only used with REFRACTORS up to 100mm aperture.
About Visual Observation:
- The bandpass of CaK (393.3 nm) is almost invisible to the human eye, hence, the Antlia Solar Discover 5Å CaK assembly is primarily used for solar imaging and not recommended for visual observation due to the difficulty of many to visually see information that CaK has to offer.
- In addition, the IR coating range of Antlia products is slightly different from the ISO 12312-2 Standard for Solar Viewers, please see the following chart and refer to ISO 12312-2 Standard for Solar Viewers (https://eclipse.aas.org/eye-safety/iso12312-2)
- For tough technical requirements and safety considerations, Solar Discover 5Å CaK assembly is not recommended for visual observation.If you need to use the product for visual observation, it is important to ensure that all filters built into the assembly are in good condition for safety.
Warranty:
- 3 years
- Disassembly of the assembly is prohibited and voids warranty. Any repair/returns/exchange for this item is not accepted once it has been disassembled.
| ISO12012-2 Transmittance Requirements |
Solar Antlia Transmittance Requirements (Solar Discover 5Å CaK, Solar 3nm CaK Assembly,Dualband Ha, CaK and CaH filter Assembly, ERF) |
||
| Requirements | Value | Wavelength Range | Wavelength Range |
| Tmax% | 0.0032% | 380-780nm | 380-780nm |
| Tmin% | 0.000061% | ||
| Tmax% (UVB) | 0.0032% | 280-315nm | 280-315nm |
| Tmax% (UVA) | 0.0032% | 315-380nm | 315-380nm |
| Tmax% (IR) | 3% | 780-2000nm | 780-1700nm |
Other Information
- Country of Manufacture: China
The Antlia Solar Discover 5Å CaK assembly incorporates a set of light-reducing filters to limit solar heat ingress for safe operation during solar imaging. It is specifically engineered to enhance imaging contrast of plage, light bridges, features prominent in the CaK 393.3nm line as well as sunspots.
The Antlia 5Å Ultra Narrow Bandpass Filter features a clear aperture of 12mm (B1200) and a wavelength centered on the Calcium II K-Line at 393.3nm. With its ultra-narrow full width half maximum (FWHM) of 0.5nm, it enables the capture of details in the Sun's chromosphere.
Installation is similar to the Antlia CaK 3nm Solar Herschel Wedge with the assembly placed between the telescope and camera. The unit is CNC machined from aircraft aluminum and oxidized. The filters are assembled within a fully enclosed tube, preventing stray light from entering the light path.
Important Notes:
- If you do not use a barlow lens, your telescope must have a focal ratio >7.
- Optional 2X, 3X and 5X Antlia barlow lenses are available specifically designed for Solar Discover 5Å CaK ; please order them separately if required. Please refer to the installation diagram.
- Optional adjustable aperture diaphragm is available with Dia 2.0mm-25mm. Antlia specifically designed this accessory for Solar Discover 5Å CaK; please order them separately if required.
- Optional 50mm and 70mm extension tubes are provided by Antlia for better focus. Please order them separately if required.
- When you are using a diagonal mirror, or barlow lens supplied by another manufacturer, the ERF filter must be installed in the correct position for safe operation. Please refer to the installation diagram.
- When you are using a telescope with an aperture >100mm, you need to use additional light reduction solutions, such as ERF filters, solar safety films which lower the telescope aperture for safe operation while using Solar Discover 5Å CaK; If without the extra light reduction solution, the Solar Discover 5Å CaK can only used with REFRACTORS up to 100mm aperture.
About Visual Observation:
- The bandpass of CaK (393.3 nm) is almost invisible to the human eye, hence, the Antlia Solar Discover 5Å CaK assembly is primarily used for solar imaging and not recommended for visual observation due to the difficulty of many to visually see information that CaK has to offer.
- In addition, the IR coating range of Antlia products is slightly different from the ISO 12312-2 Standard for Solar Viewers, please see the following chart and refer to ISO 12312-2 Standard for Solar Viewers (https://eclipse.aas.org/eye-safety/iso12312-2)
- For tough technical requirements and safety considerations, Solar Discover 5Å CaK assembly is not recommended for visual observation.If you need to use the product for visual observation, it is important to ensure that all filters built into the assembly are in good condition for safety.
Warranty:
- 3 years
- Disassembly of the assembly is prohibited and voids warranty. Any repair/returns/exchange for this item is not accepted once it has been disassembled.
| ISO12012-2 Transmittance Requirements |
Solar Antlia Transmittance Requirements (Solar Discover 5Å CaK, Solar 3nm CaK Assembly,Dualband Ha, CaK and CaH filter Assembly, ERF) |
||
| Requirements | Value | Wavelength Range | Wavelength Range |
| Tmax% | 0.0032% | 380-780nm | 380-780nm |
| Tmin% | 0.000061% | ||
| Tmax% (UVB) | 0.0032% | 280-315nm | 280-315nm |
| Tmax% (UVA) | 0.0032% | 315-380nm | 315-380nm |
| Tmax% (IR) | 3% | 780-2000nm | 780-1700nm |
The Antlia Solar Discover 5Å CaK assembly incorporates a set of light-reducing filters to limit solar heat ingress for safe operation during solar imaging. It is specifically engineered to enhance imaging contrast of plage, light bridges, features prominent in the CaK 393.3nm line as well as sunspots.
The Antlia 5Å Ultra Narrow Bandpass Filter features a clear aperture of 12mm (B1200) and a wavelength centered on the Calcium II K-Line at 393.3nm. With its ultra-narrow full width half maximum (FWHM) of 0.5nm, it enables the capture of details in the Sun's chromosphere.
Installation is similar to the Antlia CaK 3nm Solar Herschel Wedge with the assembly placed between the telescope and camera. The unit is CNC machined from aircraft aluminum and oxidized. The filters are assembled within a fully enclosed tube, preventing stray light from entering the light path.
Important Notes:
- If you do not use a barlow lens, your telescope must have a focal ratio >7.
- Optional 2X, 3X and 5X Antlia barlow lenses are available specifically designed for Solar Discover 5Å CaK ; please order them separately if required. Please refer to the installation diagram.
- Optional adjustable aperture diaphragm is available with Dia 2.0mm-25mm. Antlia specifically designed this accessory for Solar Discover 5Å CaK; please order them separately if required.
- Optional 50mm and 70mm extension tubes are provided by Antlia for better focus. Please order them separately if required.
- When you are using a diagonal mirror, or barlow lens supplied by another manufacturer, the ERF filter must be installed in the correct position for safe operation. Please refer to the installation diagram.
- When you are using a telescope with an aperture >100mm, you need to use additional light reduction solutions, such as ERF filters, solar safety films which lower the telescope aperture for safe operation while using Solar Discover 5Å CaK; If without the extra light reduction solution, the Solar Discover 5Å CaK can only used with REFRACTORS up to 100mm aperture.
About Visual Observation:
- The bandpass of CaK (393.3 nm) is almost invisible to the human eye, hence, the Antlia Solar Discover 5Å CaK assembly is primarily used for solar imaging and not recommended for visual observation due to the difficulty of many to visually see information that CaK has to offer.
- In addition, the IR coating range of Antlia products is slightly different from the ISO 12312-2 Standard for Solar Viewers, please see the following chart and refer to ISO 12312-2 Standard for Solar Viewers (https://eclipse.aas.org/eye-safety/iso12312-2)
- For tough technical requirements and safety considerations, Solar Discover 5Å CaK assembly is not recommended for visual observation.If you need to use the product for visual observation, it is important to ensure that all filters built into the assembly are in good condition for safety.
Warranty:
- 3 years
- Disassembly of the assembly is prohibited and voids warranty. Any repair/returns/exchange for this item is not accepted once it has been disassembled.
| ISO12012-2 Transmittance Requirements |
Solar Antlia Transmittance Requirements (Solar Discover 5Å CaK, Solar 3nm CaK Assembly,Dualband Ha, CaK and CaH filter Assembly, ERF) |
||
| Requirements | Value | Wavelength Range | Wavelength Range |
| Tmax% | 0.0032% | 380-780nm | 380-780nm |
| Tmin% | 0.000061% | ||
| Tmax% (UVB) | 0.0032% | 280-315nm | 280-315nm |
| Tmax% (UVA) | 0.0032% | 315-380nm | 315-380nm |
| Tmax% (IR) | 3% | 780-2000nm | 780-1700nm |
Other Information
- Country of Manufacture: China
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Hide Found a better Shipped Price on Frontend? | No |

Antlia 1.25" & 2" Solar Discover 5Å CaK Assembly


















