What solar features can I image with the Antlia Solar Discover 5Å CaK assembly?
This assembly is designed to capture high-contrast details in the Sun's chromosphere. Antlia engineers it to enhance imaging contrast of plages (bright regions often near sunspots), light bridges that form across sunspot umbrae, sunspots, and other features prominent in the CaK 393.3nm line.
Do I need an additional filter to use the Solar Discover 5Å CaK on my 80mm f/7 refractor?
An 80mm refractor is below the 100mm aperture limit, so Antlia does not require extra light reduction for the aperture. But f/7 does not meet the requirement to be slower than f/7 without a Barlow, so use one of Antlia's 2X, 3X or 5X Barlow lenses. If you use a zenith mirror or another manufacturer's Barlow, the ERF filter must be installed in the correct position shown in Antlia's installation diagram.
How do I safely use the Antlia Solar Discover 5Å CaK assembly with my 120mm APO refractor?
Because your telescope's aperture is greater than 100mm, Antlia requires an additional light reduction solution for safe operation, such as ERF filters, solar safety films, or lowering the telescope aperture. Without a Barlow, your telescope must also be slower than f/7.
Why is the Antlia Solar Discover 5Å CaK assembly not recommended for visual use?
The filter isolates light at 393.3nm, a wavelength at the extreme edge of human vision that is almost invisible to the eye. Its IR coating range also differs slightly from the ISO 12312-2 Standard for Solar Viewers, and Antlia does not recommend it for visual observation for technical and safety reasons. Use it for imaging.
What is the purpose of the optional 2x, 3x, and 5x Barlows for the Solar Discover 5Å CaK?
The Antlia-designed Barlow lenses serve two functions. First, they increase the effective focal length of your telescope, which magnifies the image for higher-resolution captures of smaller solar features. Second, without a Barlow your telescope must be slower than f/7, so a Barlow is needed if your telescope is f/7 or faster.
Can I use my own Barlow lens with the Antlia Solar Discover 5Å CaK assembly?
Antlia's 2X, 3X and 5X Barlows are designed specifically for this assembly. When you use a Barlow lens supplied by another manufacturer, or a zenith mirror (star diagonal), the ERF filter must be installed in the correct position for safe operation; follow Antlia's installation diagram, and contact us if you are unsure.