IDAS NB1 Contrast Boost Triple Line-Pass Narrowband Filter Triple band-pass – Ha, Hb & OIII Various sizes Made in Japan IDAS NB Filters are designed to enhance the contrast of emission nebula, yet accommodate the filter spectral shift* when used with modern fast optical systems. Features include: Ideal flat-top and moderate Band-pass Excellent in-band transmission Extremely steep Band-pass edges minimize internal reflections Near IR (NIR) is blocked up to 1100nm Available in 52mm and 48mm sizes 2.5mm thickness (Par focal with other IDAS LPS filters) IDAS-proprietary IGAD/MBT/UFP quality Made in Japan * All interference filters are subject to a Band-pass spectral shift which depends on the angle of incidence of the incoming light. IDAS NB filters are designed to accommodate the spectral shift of modern fast optical systems. When placed in front of an optical system, the spectral shift is determined by the focal length of the optics and the size of the imaging sensor. For an APS-C sensor, up to a 50mm focal length can be accommodated. For a full-frame sized sensor, up to an 80mm focal length can be used. For filters placed between the optical system and imaging sensor, the situation is more complex. IDAS NB filters are designed with modern fast optics in mind and can accommodate an angle of incidence of up to 14°. NB Filter Types Emission Lines Filter Sizes Base Filter NB1 Triple - Hβ+OIII, Hα 48mm & 52mm None required NB2 Dual - OIII, Hα 48mm, 52mm, Canon Drop-in Required* NB3 Dual - OIII, SII 48mm, 52mm, Canon Drop-in Required* * In-camera IR blocker works as the base filter.
