The Dark Clear Skies 1.25″ UHC (Ultra High Contrast) Filter is designed to enhance the visibility of emission nebulae by selectively transmitting key nebular wavelengths while suppressing background skyglow and common sources of light pollution.
Purpose & Use
UHC filters are widely used in astronomy to improve contrast between emission nebulae and the surrounding sky. By reducing unwanted wavelengths from artificial lighting and natural skyglow, this filter helps nebular detail stand out more clearly during visual observing and astrophotography.
Key Features
- Enhances contrast of emission nebulae
- Suppresses common light pollution wavelengths
- High transmission at key nebular emission lines
- Standard 1.25″ mounted filter format
- Suitable for visual astronomy, imaging, and EAA
Compatibility
Designed to fit standard 1.25″ (M28.5 × 0.6) filter threads commonly used in eyepieces, filter wheels, and imaging adapters.
Typical Applications
- Visual observation of emission nebulae
- Deep-sky astrophotography
- Electronically Assisted Astronomy (EAA)
- Observing under suburban or urban skies
Technical Specifications
| Filter Type | UHC (Ultra High Contrast) |
| Filter Size | 1.25″ (M28.5 × 0.6) |
| Clear Aperture | Approx. 26 mm |
| Substrate | Optical-grade glass |
| Coatings | Multi-layer interference coatings |
| Filter Cell | Anodised aluminium |
| Application | Visual astronomy, astrophotography, EAA |
If you are unsure whether a UHC filter is suitable for your observing or imaging setup, feel free to contact u