The IDAS HEUIB-II (H-alpha Enhanced UV IR Blocking) filter is designed for enhanced spectrum DSLRs and one-shot color CCD astronomical cameras.
Besides removing the IR and UV ends of the spectrum which are often out of focus in refractive optics, it isolates the common H-alpha line relative to the surrounding extreme red end of the spectrum, making it easy to bring out the faint H-alpha emission nebulosity of astronomical photos, yet retain the background color balance of broadband photos.
IDAS filters are developed for astrophotography
Unlike other astronomical UV-IR blocking camera 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, but retains high sensitivity for the important H-alpha emission line.
The original camera filter blocks large part of the red spectral region, including H-alpha, most astronomical UV/IR blocking filters let all red light pass, resulting in reddish appearance.
The HEUIB-II lets light around H-alpha pass and balances this by a reduced transmission from orange to light red. Thus the camera can be used for astrophotography and for daytime photography without any modification in between!
Main characteristics of the IDAS HEUIB-II filter:
♦ Especially designed for DSLR and single-shot CCD colour cameras
♦ High quality anti-reflective coatings