DGM Optics 1.25" NPB Nebula Filter-Cosmetic 2nd The NPB is the ONE filter to have if you have just one, and now regarded as the top narrowband (UHC type) filter in the world. Judged by renown astro-equipment author Phil Harrington as the best of nine leading competitors in the Astronomy Magazine review "Secret Weapons" (August 2005). With the NPB more objects show enhancement, than any other filter in it`s class. Bright nebula seem to be "switched on" with this top shelf filter designed by Dan McShane, Optical Thin Film expert and founder of DGM Optics. One observer described the NPB as a "UHC on steroids"! And, with ultra durable Ion Assisted Plasma Coating Technology used to produce your NPB Filter, it will provide decades of flawless performance.