Moravian instruments, Inc., source: https://www.gxccd.com/art?id=380&lang=409, printed: 28.03.2024 21:52:52

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New adapter for Canon EOS bayonet capable to hold DSLR Clip-filters
 Usage of various filters in combination with color detectors of digital single-lens reflex cameras (DSLRs) is often limited to filters suppressing light pollution. Still, there are various filters intended for placing directly inside the DSLR camera bodies, called clip-filters. These filters are fixed on place using flexuous parts of their thin cells. Moravian Instruments newly introduce a variant of Canon EOS bayonet adapter, capable to hold these clip-filters.

CCD cameras of G2 series can include integrated filter wheel for 5 filters up to 31 mm diameter. So changing of filters between exposures can be performed programmatically, without the user's intervention. Camera can interleave acquisitions of individual R, G and B images, for instance to eliminate influence of changing light conditions, height of object above horizon etc. But the number of filters in internal filter wheel is limited to five.

While it is often enough to accumulate several tens of minutes of exposure for each color channel to obtain good image of many objects, and so it is possible to get the whole exposure during one night, exposures for narrow-band imaging (typically in wavelengths corresponding to SII, H-alpha and OIII lines) must be much longer. The it could be possible to combine LRGB filters in internal filter wheel with narrow-band filters in the form of clip-filters. When an exposure through single narrow-band filter takes whole night, automatic filter exchange is not that necessary.

G2-8300 CCD camera EOS adapter for clip-filters

G2-8300 CCD camera EOS adapter for clip-filters

Because of clip-filters dimensions (they are rectangular with approx. 27 × 22 mm size), they are limited to G2 series of CCD cameras only. It is not possible to use them with large-sensor cameras of G3 and G4 series.

Inserting of clip-filter int the adapter (left) and G2 camera with the filter on place (right)