Current Price: $139.95
Buy It Now Price: $139.95
Bids: 0

Hydrogen Alpha (Ha) 12nm Filter
Fits Canon EOS Series DSLR
I've recently upgraded from a Canon 60Da DSLR to a dedicated cooled
astronomy camera for my observatory, so I'm selling the filter.

filter has been a lot of fun even on a fairly bright moonlit sky. The
exposures come out nicely, but you need to go a log longer on exposure
times since the filter is dark, and mainly ends up on the red channel of
your color camera (in my case a DSLR).

I've recently moved from W.
Washington skies to darker skies in Wisconsin (which is a nice change
from the wet and light polluted Seattle skies!) and upgraded to an
ASI294 camera. This filter only fits into a Canon EOS family of DSLR
cameras, so I'll be replacing it with a threaded filter that fits my new

I mainly did "visible" light imaging with some occasional Ha
imaging, so this filter is in excellent condition. Always carefully
stored in the case when not used.

Technical Data (from Astronomik web page)

  • Guaranteed Transmission of more than 90% at the H-alpha Line (656 nm)
  • Typical Transmission of 96% at the H-alpha Line (656 nm)
  • Full-Width-Half Maximum (FWHM): 12nm
  • perfect blocking of unwanted light from UV up to the IR
  • parfocal with all Astronomik filters
  • MFR Coating technique: Usable with all optics up to f/3
  • Thickness of 1mm
  • Not sensitive to moisture, scratch resistant, not aging
  • optically polished substrate, striae-free and free of residual stresses
  • High quality storage box


  • Excellent condition.
  • When not in the camera, it was always stored in the case for protection.
  • See attached photos - all taken recently from my location in Sturgeon Bay, WI

Payment and shipping: 

  • Payment - PayPal
  • Ships from 54235 Sturgeon Bay, WI
  • Wisconsin buyers - we have to add 5.5% sales tax
  • USPS Priority Mail.
  • Shipping weight approximately 6 oz packaged

Our Terms:

  • Listing: We have listed this item to the best of our ability. If you have any questions, please contact us and we can provide additional photos, or answers to your questions.
  • Payment: Payment is expected within three days of the ending or mutually agreed on price (or let us know otherwise), PayPal is the preferred method.
  • Shipping: Allow up to 3 business days after payment has been received.  We are often on the road picking up inventory during the week.  Our shipping days are Mondays and Thursdays, although smaller items will often go out sooner (we do have a big mailbox!).  In most cases, we ship with the most economical method (FedEx or USPS), if you desire a faster or express shipment, please let us know so we can accommodate your request.
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Ebay Sellers Since 1999

Filed under: Eyepieces & Accessories