ZWO Narrowband 7nm 36mm Filter Set

The ZWO 7nm Narrowband Filter Set (36mm) combines H-alpha, S-III and O-III filters. This narrowband filter set's purpose is for observing nebulae, in particular. These filters should increase the contrast and are not used to increase the target's brightness or reduce the amount of light pollution. 

Technical Parameter:

Size: D=36mm

Thickness: 2mm

Technical Data

• FWHM：7±0.5nm
• Glass Thickness 2.0+/-0.03 mm (1.25”/31mm/36mm)
• Optics are polished in order to achieve 1/4 wavefront
• Allows 90% transmission - H-alpha line 656nm (H-Alpha filter )
• About 90% transmission - SII line 672nm (SII filter )
• About 90% transmission - OIII line 500nm (OIII filter )
• Infrared wavelength at 700-1100nm cut-off
• <0.1% transmission of off-band, OD3(Optical Density)

The ZWO 7nm Narrowband Filter Set (36mm) combines H-alpha, S-III and O-III filters. This narrowband filter set's purpose is for observing nebulae, in particular. These filters should increase the contrast and are not used to increase the target's brightness or reduce the amount of light pollution. 

Technical Parameter:

Size: D=36mm

Thickness: 2mm