Filter

Optolong L-Ultimate

Dual-band narrowband filter

Ha

656.3nm + OIII 500.7nm

3nm FWHM each band

Blocking 300-1000nm, greater than OD4

1.85mm optical glass, 60/40 surface quality, lambda/4 transmitted wavefront

2-inch mounted (also 1.25-inch)

For OSC, DSLR, CMOS and CCD cameras

Optimised for fast optics with low halo