Skip to content

ZWO Cameras 10% Off!

Astronomik SII 12 nm CCD EOS Clip Filter - SII-EOS

shipping truck Free shipping
SKU: ASF-SII-EOS

Astronomik SII 12 nm CCD EOS Clip Filter

  • With an EOS Clip frame format, this Astronomik SII 12 nm CCD Filter is designed specifically for astrophotography with Canon EOS cameras that have an IR blocking filter over their detector
  • Design especially for CCD astrophotography applications
  • Created to the highest technical standards for the premium optical performance needed to use your Canon EOS camera for deep sky imaging
  • Allows light from ionized sulfur (SII) emissions to be transmitted while blocking almost the complete remainder of the visual spectrum plus IR
  • FWHM bandwidth of nearly 12 nm
  • An excellent filter for planetary nebulae and supernovae residue imaging
  • Made in Germany, a country recognized for producing high quality optics!


More About Astronomik SII 12 nm CCD Filters


This SII 12 nm CCD EOS Clip Filter from Astronomik is an ultra narrow emission line filter made to be used with Canon EOS DSLR cameras as well as instruments as fast as f/3.5 for CCD astrophotography operations only. Does not work for visual or solar applications. This filter permits ionized sulfur (SII) light from emission nebulae to be transmitted to your sensor while completely blocking the remainder of the spectrum, making it ideal for use in light polluted environments.

With a 12 nm FWHM (full width at half maximum), this filter is optimal for typical CCD cameras, enabling the use of super fast optics. The ideal aperture ratio range for this filter's usage is 1:2.8 to 1:15 with apertures of 6" (150 mm) and above. The Astronomik SII 12 nm CCD Filter has a transmission of up to 99%, a figure that cannot be achieved by simply stacking additional narrowband filters. Transmission losses and chromatic aberrations, which can be an issue with other filters, only occur with Astronomik filters in the case of extremely bright aperture ratios of 1:2 or more being involved. An additional benefit of 12 nm filters is the enhanced guide star possibilities for cameras with a built-in autoguider.

When compared with 6 nm filters, 12 nm filters provide similar performance. However, with 12 nm filters, background stars maintain their sharpness, while 6 nm filters offer a higher contrast gain. Therefore, it is best to use both filters together to achieve maximum contrast without compromising the quality of the background in your final image.

As with all Astronomik filters, the SII 12 nm EOS Clip Filter is parfocal with all other Astronomik filters. This filter is also remarkably resistant to potential damage that can be caused by scratching, aging, and high humidity. All Astronomik filters are delivered in a durable, high quality plastic storage case.

Astronomik Clip Filter System


Astronomik's exclusive Clip-Filter system is made from black anodized aluminum and laser-cut using ultra modern machinery. This filter can be directly inserted into the camera body of a Canon EOS DSLR in just seconds. No modifications are required and all lens functions such as focus, screen, and image stabilization, continue to be operational! With the exception of the EF-S series, all Canon system lenses, as well as all M42 and T2 lens adapters, are suitable for the Astronomik EOS Clip Filter. In addition, this system also serves as a dust protector, preventing dust from accumulating on your sensor during long exposures.

List of Compatible Canon EOS Cameras

Canon EOS
 Suitable for Clip-Filter? 
 LiveView? 
7D MkII
Yes
Yes
7D
Yes
Yes
20D
Yes
No
20Da
Yes
Yes
30D
Yes
No
40D
Yes
Yes
50D
Yes
Yes
60D + 60Da
Yes
Yes
70D
Yes
Yes
77D
Yes
Yes
80D
Yes
Yes
300D / Digital Rebel / Kiss Digital
Yes
No
 350D / Digital Rebel XT / Kiss Digital N 
Yes
No
 400D / Digital Rebel XTi / Kiss Digital X 
Yes
No
450D / Rebel XSi / Kiss X2
Yes
Yes
500D / Rebel T1i / Kiss X3
Yes
Yes
550D / Rebel T2i / Kiss X4
Yes
Yes
600D / Rebel T3i / Kiss X5
Yes
Yes
650D / Rebel T4i / Kiss X6
Yes
Yes
700D / Rebel T5i / Kiss X7
Yes
Yes
750D / Rebel T6i / Kiss X8
Yes
Yes
760D / Rebel T7i / Kiss X9
Yes
Yes
1000D / Rebel XS / Kiss F
Yes
Yes
1100D / Rebel T3 / Kiss X50
Yes
Yes
1200D
Yes
Yes
1300D
Yes
Yes
2000D
Yes
Yes
100D
Yes
Yes
200D
Yes
Yes