The Astronomik narrowband line filters with MFR coating are perfectly tailored to the needs of astrophotography: maximum contrast, minimal stray light, no halos and the finest star images. With the new Astronomik MFR narrowband line filters, you get raw data of the highest quality: the optimal starting point for further processing into impressive astrophotography!
For the best possible yield of valuable night-time observation time, maximum filter transmission is of course required: The guaranteed transmission of the narrowband line filters is 90%, the typical transmission of the filters delivered is 96% - these values apply to both the 12nm filters and the 6nm version!
Unlike filters from other manufacturers, the transmission curve of Astronomik narrowband line filters shifts only minimally when used with fast optics. While other manufacturers offer special "high-speed filters" or even require you to purchase a new filter for each aperture ratio, you can use the new Astronomik narrowband line filters with MFR coating on almost all instruments: All line filters with a 12 nm half-width (FWHM) can be used up to an aperture ratio of f/3. All line filters with a 6 nm half-width can be used up to an aperture ratio of f/4.
Photography with narrowband line filters: If you have to observe under a bright sky, line filters are usually the best way to get started in astrophotography and take successful pictures, as light pollution is no longer a problem. A H-alpha filter is usually a sensible first purchase: with this filter, you can easily take deep images even when the moon is full or the sky is extremely bright!
Which half-width is right for me? When shooting from the city, images taken with a DSLR and even with many cooled CCD cameras are limited by the dark current of the camera and not by the background brightness of the sky. In this case, further suppression of the sky background by a lower half-width will not reveal any more details in the object! Compared to the 6 nm filters, the 12 nm filters have the advantage that they usually find tracking stars with cameras with built-in tracking sensors! If you have a camera with extremely low dark current and good cooling, the 6 nanometre filters offer all their advantages: Even stronger suppression of sky brightening allows even longer exposure times and thus even deeper shots! Due to the low half-width, the stars become tiny, and faint stars disappear almost completely. Especially in Milky Way regions with many stars, the 6 nanometre filters allow even faint objects to be displayed with high contrast without getting lost in the swarm of stars.
In short: We recommend using 12 nm filters for DSLRs and all cameras with limited dark current. The 6 nm filters are the right choice in locations with exceptional light pollution, for cameras with extremely low dark current, and when faint objects require maximum contrast in the image!
Filter size 31 mm: This filter fits perfectly into all filter wheels for 31 mm from ZWO, QHY, QSI, Starlight Xpress, SBIG, Moravian and Atik. The design with a protective ring and blackened filter edges prevents stray light, protects the filter mechanically and makes it easier to handle. The orientation of the filter in the filter wheel is irrelevant.
