Astronomik UHC 1.25" (M28.5)
Key specifications
| Filter type | Light Pollution |
|---|---|
| Passband | 480-505nm + above 645nm |
| Bandwidth | 25 nm |
| Filter size | 1.25" |
| Mounted | Yes |
About
An Ultra High Contrast filter passing the OIII and H-beta lines at near 100% while blocking sodium and mercury street lighting and natural airglow, lifting gaseous and planetary nebulae out of the sky background from city or dark sites. Usable from f/3 to f/15. 1.25" M28.5 mount.