Anti-Halo PRO Dual-Band 2″ Ha+OIII filter
Frame thickness: body 5mm+ thread 2.5mm, a total of 7.5mm
Filter glass: 1.85mm
Ha CWL: 656.3nm Band Width: 3.7±0.5nm
OIII CWL: 500.7nm Band Width: 3.2±0.5nm
Blocking depth: OD5 (200-1100nm)
In recent years, not only the single narrowband filters are chasing narrower band width, but also the dual band filters. From 7nm to 3nm, from a manufacturing process improving so fast!
But one thing is missing, halo control! The halo around stars is a nightmare when you shoot some famous deepsky object!
Vega testing of halo control
Luke use his 8″ F4 Newtonian and Canon 700D to test Anti-Halo Pro dual-band filter, the target is Vega (Zero magnitude star), exposure 120sec. We can see there is no halo around Vega, the off axis big halo is the reflection of the lens in coma corrector.
NGC7822, Luke Newbould, Esprit120APO+Anti-Halo Pro Ha+OIII filter + Poseidon-C Pro
NGC7000, Luke Newbould, Redcat 51APO+Anti-Halo Pro Ha+OIII filter + Canon 700D