Hutech IDAS LPS-P2 Light Polution filter 50,8mm (2 inch) - LPS-P2-48
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
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)