Do you observe from an urban, light-polluted location, but still want to observe mysterious nebulae, galaxies and star clusters? If you're a lover of deep sky objects, then a variety of deep sky filters are almost a must-have accessory. By using these filters, deep sky objects can reveal details that would not be visible without a filter, or only from a very dark sky.
The Astronomik CLS is a general-purpose, broadband deep sky filter that is particularly suitable for both visual and photographic applications to reduce the harmful effects of light pollution. The filter can be purchased in two versions: the CCD version includes a UV/IR blocking layer, which is essential for photographic use when no such filter is available in front of the camera (e.g. astronomical CCD cameras, DSLR camera with filter removed). For visual use or a DSLR camera that has undergone a Baader filter change, any filter version can be used, in which case the CCD one has no advantage.
The principle of operation of the Astronomik CLS filter is quite simple: it only passes certain wavelengths of incoming light, preventing light from disturbing artificial light sources (e.g. sodium and mercury vapour lamps). The result is that the contrast between the sky background and the observed object is increased, so that faint details can be observed. All Astronomik deep sky filters are manufactured with maximum care and precision, so that thecontrast and light transmission are as good as possible. The extremely precisely polished glass material and the interference layer, vapor-deposited in about 130 layers, clearly set these filters above their competitors. Another advantage is their extraordinary scratch resistance, which is why they retain their transmission characteristics even after many years of intensive use. Thanks to their premium quality materials and machining, Astronomik filters do not degrade the image at all. Unlike cheaper filters, Astronomik filters keep stars completely point-like.
EOS clip version
The EOS-clip version of the filter is designed specifically for owners of EOS SLRs. Thanks to its unique solution, the filter can be clipped simply by hand into Canon EOS cameras without any tools or accessories. This makes it possible to take astrophotographs not only through telescopes, but also with telephoto lenses that can be attached to the camera. The clip-on filter can be used with almost all lenses on the market, except Canon lenses with the EF-S designation. Unlike photographic filters, they transmit IR range, so for photographic use we recommend using an IR block filter in addition to the visual filters.
All Astronomik deep sky filters come with a 10 year full warranty!