The Altair Dichroic Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging ...
The Altair Dichroic Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging or observing with your Daystar Hydrogen Alpha Quark, or other Hydrogen Alpha Etalon filters.
Reduces approx. 98% of heat reaching the optics to keep Etalon from drifting off-band and protect your equipment.
30nm FHWM Bandpass at H-alpha (H) wavelength of 656.28 nm (Full Width Half Minimum) Transmission: ~95.5%
40nm FHWM Bandpass with CWL at 395nm covering Calcium H-Line and Calcium K-Line wavelengths. Transmission: ~90.5%
UVIR blocking OD3 0.1% @400-1100nm blocking over 98% of heat to your 3rd party Etalon at eyepiece or camera end, E.g. Daystar Quark). Please note it's your responsibility to use a proper commercial Etalon with this product, and to follow the manufacturer's instructions.
Visible light blocking: OD4 0.01% @400-700nm to reduce reflection effects and over 98% of heat.
Diameter 140mm Thickness 12.0mm (required to achieve surface precision)
Multilayer coatings with SiO2 protective overcoat.
ERF Holder cell included with soft tip threaded knobs. Tough and very light, easy to disassemble for cleaning the filter with optical wipes. Cell does not put any tension on the optics.
The Altair Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging or observing with your Daystar Ha Quark, or other Etalon filters.
The Altair Dichroic Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging ...
The Altair Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging or observing with your Daystar Ha Quark, or other Etalon filters.
The Altair Dichroic Solar Energy Rejection Filter or D-ERF protects your telescope and solar imaging equipment from excessive heat build-up when solar imaging or observing with your Daystar Hydrogen Alpha Quark, or other Hydrogen Alpha Etalon filters.
The Altair 1.25" Solar Continuum filter Enhances sunspots, granulation, and fine photosphere detail. For use with Baader Solar Filter or Herschel Wedge.