ERF-Filter
- Home /
- Observe the Sun /
- Optical Accessories /
- ERF-Filter
ERF-Filters
ERF (Energy-Rejection-Filter) are essential components for solar observation. They protect the telescope and eyes from the high-energy radiation (IR heat radiation, UV radiation) and enable narrow-band filtering for observation and photography.
The filter reflects heat radiation and is designed for small refractors and camera lenses. It is necessary for H-alpha and calcium solar photography.
- 2" filter thread with M48x0.75 external thread - low profile mount
- Suitable for use in front of the H-alpha or calcium attachment for refractors up to 100mm aperture
- Suitable for small camera lenses or refractors in front of the lens
- 25 nm transmission in the H-alpha and calcium range - Transmission 90
- Min. 1/4 lambda accuracy - plane-parallel discs in high quality cell
149.00 €
Estimated delivery time : Unbekannte Lieferzeit
