Telescope-Accessories-Astronomik OIII 12 nm CCD Filter – EOS Clip

Astronomik OIII 12 nm CCD Canon EOS Clip Filter

• The Astronomik OIII 12 nm CCD Filter – EOS Clip is made for astrophotography

• This filter has a Transmission of nearly 100% in the OIII line

• FWHM bandwidth of roughly 12 nm

• The ideal filter for imaging planetary nebulae and supernova remnants

• Coatings offer exceptional protection against scratching, aging, and humidity

• Diffraction limited, the filter will not reduce the optical performance of your telescope

• Made in Germany, a country renowned for their optical quality!

More About the Astronomik OIII 12 nm CCD Filter – EOS Clip

The Astronomik OIII CCD filter is a narrow band emission-line-filter for CCD photography. The filter lets the light of double ionized Oxygen of emission nebulae pass and blocks nearly the whole remainder of the spectrum where the CCD is sensitive. The full width at half maximum (FWHM) of 12 nm is ideal for common CCD cameras and allows the use of very fast optics. The optimal aperture ratio for the use of the filter is 1:3 to 1:15. It should be noted that the filter has a transmission of up to 99%, which cannot be attained by stacking more narrow-band filters. A further note, which led to selecting the half width (FWHM), is the dark current of common CCD imagers. Exposures with a CCD cooled to -15°C are limited by the dark current of the CCD, even in large cities with a bright background. Another advantage of the 12 nm filter is the better availability of guiding stars for cameras with built-in-autoguider.

The Astronomik OIII CCD increases the contrast between objects, in this case between the OIII emission line and the skyglow background. Our Astronomik OIII CCD completely suppresses the emission lines of artificial lighting (mercury (Hg) and sodium (Na)) and skyglow. Transmission losses and chromatic distortions, which arise with other filters, only occur with Astronomik filters when extremely bright aperture ratios of 1:2 and more come into play. The filter has a built-in IR-blocker up to 1150 nm. You don’t need an additional IR-blocker with this filter.

When using the Astronomik OIII 12 nm CCD – EOS Clip filter together with the H-alpha, and the SII CCD filters you can obtain three-color images of emission line objects (gas nebulae) from locations with very strong light pollution. To do so, you would take an image in three different wavelengths, select each one as a color-channel in Photoshop and paste them together as one single color image. Diffraction limited, the filter will not reduce the optical performance of your telescope! Astronomik filters are delivered in a high-quality, long lasting, plastic filter box.

Astronomik EOS Clip Filter System

Made from black anodized aluminum and laser-cut on state-of-the-art machines, Astronomik’s unique Clip-Filter system can be placed directly into the camera body of the Canon EOS in only seconds. Adjustments are not needed, and all lens functions such as focus, screen, and image stabilization, stay operational! Excluding the EF-S series, all Canon system lenses, as well as all M42 and T2 lens adapters, are compatible with the Astronomik EOS Clip Filter. This system also serves as a suitable dust shield, preventing dust from gathering on your sensor when taking long exposures.

Transmission Specifications

• 99%+ transmission for both of the OIII lines

• Blocks unwanted wavelengths in other parts of the visible spectrum