Similar to conventional luminance filters but with brighter images, the Alpine Astronomical Baader UHC-S Nebula Filter produces ultra-high contrast when viewing or imaging nebulae.
When installed on smaller 4-10"-aperture optical tube assemblies (OTAs), users will appreciate the high 97%+ transmission efficiency that ensures views remain bright and crisp. Larger-aperture users will greatly value the rich star fields that are left in view and subtle nebular shading details that are revealed. This performance differs from traditional deep sky filters, which tend to eliminate star fields, making images of nebulae appear flat and out of context against the stark blackness of starless space. By its nature, the UHC-S has natural light pollution filtration, helping to eliminate emissions from street lights and improving views in most urban areas.
Helping to boost transmission are scratch-resistant multi-coatings and planeoptically polished surfaces, which work together for maximum throughput and uniform edge-to-edge transmission. This version of the filter is offered here mounted in a frame that has been threaded to fit standard 2" eyepieces and accessories for projection and afocal imaging techniques.