This item has been used 1 time so it's like new
- Dual Narrow bandwidth H-Alpha/O-III 7nm narrowband filter properly designed for astrophotography both in light polluted
- Take color images without needing to combine images with multiple filters
- Useful for imaging emission nebulae, planetary nebulae and supernova remnants
- Designed to sharply cut off the inference of artificial light from sodium vapor or mercury vapor street lights and other unwanted disturbance like sky glow
SPECIFICATIONS
| Brand | SVBONY |
| Model | SV220 |
| Name | Duo-Band OSC Filter |
| Size | 1.25-Inch |
| Substrate Thickness | 1.80mm |
| Clear Aperture | 44mm |
| Wavelength Range | 300-1100nm |
| FWHM | OIII (7nm) & HA (7nm) |
| Blocking | OD5 |
| Peak transmittance | 500.7nm@T>90%; 656.3nm@T>94% |
| Surface Quality | 60/40 |
| Surface parallelism | 1/4λ |
| Thread | M48x0.75 |
| Single Thread | Yes |
| Net Weight | 12.5g / 0.44oz /0.027lb |