IDAS LPS P2 nebula filter - Filter for the Deep Sky Photography
... special Version for Canon DSLR cameras
Camera Body Front Filters
For selected enhanced-spectrum digital cameras, camera body front filters are available for quick field modification of the camera's spectral response. Camera bodies for which front-filters are available are:
Canon Rebel (300D), Rebel XT (350D), XTi (400D), XSi (450D), XS(1000D), 1100D, T1i(500D), 20D, 30D, 40D, 50D, 60D and 7D
Camera body front filters are mounted in a holder which goes between the camera's lens bayonet and the viewing mirror. These may be quickly and easily inserted or removed from the camera body as required by the user. Front filters provide the additional benefit of protecting the camera's image sensor from dust accumulation.
Light pollution suppression (LPS) filters are designed to suppress the common emission lines generated by artificial lighting, yet allow the important nebula emission lines to pass, thus enhancing the contrast of astronomical objects, particularly emission nebulae (see filter plots).
Unlike other light pollution suppression filters, IDAS filters are specifically designed for balanced color transmission using the IDAS unique Multi-Bandpass Technology (MBT) process. The balanced transmission allows color photographs to be taken with minimal color cast to broadband emission objects such as stars, galaxies and globular clusters. The comparison photos at right demonstrate (qualitatively) that the IDAS filter maintains better color balance than other filters which have been designed for visual use.
CCD imaging can also benefit, because although CCD imagers can already shoot through light pollution to some extent, including an LPS filter to the setup gives an added (signal-to-noise) edge.
Front-mounted filters do not affect the camera's autofocus operation but, when installed may interfere with the proper installation of certain lenses which have parts which protrude into the camera body.
Filter transmission curve: