Astronomik H Alpha 12NM CCD Clip Filter Canon APSC
Hydrogen Alpha 12NM CCD Clip Filter for Canon APSC Sensor
The Astronomik 12 nm H-alpha CCD Clip-Filter for Canon EOS APS-C cameras is a narrow band-pass filter for hydrogen nebulae and can be inserted into the camera body within seconds.
Do you own a Canon EOS digital camera for astro-imaging? Then you have surely encountered the following problems:
♦ Large filters for large camera lens objectives are very expensive.
♦ If you place a filter holder between your camera body and lens, you loose the ability to focus to infinity.
♦ With long exposure times, your cameras sensor chip is exposed to more dust.
With the Astronomik Clip-Filter System you can take care of all of these problems at once!
The patented Astronomik Clip-Filters are made of black anodized aluminum and laser-cut on state-of-the-art machines. They can be inserted within seconds directly into the EOS camera body. There are no changes necessary and all lens functions (focus, screen, image stabilization) remain operational!
Almost all Canon system lenses (with the exception of the EF-S series) and all M42 and T2 lens adapters, can be used with the Astronomik Clip-Filter System. The Clip-Filter System also acts as an outstanding dust shield, which prevents the possibility of dust settling on the sensor during long time exposure (The MC-Clear filter does not have a filter effect and only acts as a dust shield.)
This H-alpha Filter is suitable for imaging of Hydrogen nebulas from observation sites with light pollution and from dark sites as well. The contrast between an object glowing at 656nm and the background is increased enormous!
Due to the combination of the narrow bandwidth of 12nm and the high transmission of typically 96% the filter gives you an contrast boost, as all unwanted light from other wavelengths than 656nm is blocked form UV up to the IR. This results in an very dark background compared with any filters with a higher bandwidth
The FWHm of 12nm is optimized for typical DSLR cameras with CMOS sensors and CCD cameras with a normal/high dark current: With these cameras the background signal in images taken from heavily light polluted sites is dominated by the dark current of the sensor, not by fluy coming from light pollution. In this case a further reduction of FWHM does not improve the image, as the background will not get darker. Compared to the 6nm filters you have more stars in the field of view which gives you more guiding stars when working with an integrated/dual guiding chip!
Compatibility:
Fits all Canon APSC Crop Sensors
Not suitable are cameras offered before 2003 and all varieties of the Canon EOS 1D and EOS M.
