ERF Filter 150mm Artesky (SKU: ERF-150) all astro filters opinie

1164 EUR price without VAT: 946 EUR Shop online: ● on request  Shop in Warsaw (qty): ● on request  Shop in Chorzow (qty): ● on request

CHEAP DELIVERY TO EUROPEAN COUNTRIES CHECK IT OUT!

Artesky ERF 150 mm (SKU: ERF-150 ) is a filter rejecting solar energy ( Energy Rejection Filter ), designed for telescopes for observing the Sun in the H-alpha band. Mounted on the front of the telescope, it reflects most of the heat and UV radiation, protecting the etalon filter from overheating and eliminating thermal turbulence inside the tube.

The filter is made of optical glass of very high uniformity and flatness, with a single-sided dielectric coating that precisely reflects light outside the 60 nm range around the H-alpha wavelength (656.28 nm). This design not only improves image quality, but also significantly reduces heating of coatings and optical elements.

The coatings are applied using the most modern optical sputtering machines. Thanks to this, the filter maintains the flatness of the surface, without causing image distortion. Reflection of radiation from the range of 200-1100 nm while transmitting up to 95% of H-alpha light ensures high efficiency and safety.

Note: The ERF filter cannot be used alone for visual observations - it may cause irreversible damage to the eyesight. It should be used only as part of a set for observing the Sun in the H-alpha band, together with an etalon filter (e.g. Daystar). The surface with the coating should be directed towards the Sun (marked with an arrow on the edge). Version without a cell - also available in a mount.

Key Features

• high-class filter for solar telescopes
• effective protection against heat and UV radiation
• FWHM transmission band 60 nm around 656.28 nm (H-alpha)
• high transmission in the H-alpha band: up to 95%
• optical quality: λ/4, surface finish 60-40
• highly homogeneous glass, resistant to stress
• minimal edge chipping (<0.2 mm)
• reduction of thermal turbulence in the tube
• ensures full use of the resolution of the optical system

Set components

• ERF filter with a diameter of 150 mm (without frame)

Technical parameters

• diameter: 150 mm
• glass thickness: 12 mm
• central wavelength: 656.28 nm
• bandwidth (FWHM): 60 nm
• peak transmission: 95%
• cut-off range: 200–1100 nm
• cut-off depth: OD4
• surface quality: λ/4, finish 60-40
• edge chipping: <0.2 mm