Hutech Energy Rejection Filters

Description

• The external filter prevents the telescope inside from heating up.
• High-quality interference type of filter
• 60nm bandpass (central wavelength : 656.28nm)
• Over 95% transmission at Ha emission line
• OD 4 between 200nm and 1100nm
• Glass thickness : 12.0mm
• The filter assembly is comprised with a filter holder unit and a dew-shield adapter.
• Available at 190mm, 140mm and 120mm effective apertures at this moment.
• The set comes with a customized dew-shield adapter. So perfectly fits your scope.
• The dew-shield adapters will be sold separately as an optional items later. So each user can switch ERF to another telescope by changing only the dew-shield adapter.
• A couple of weeks lead time due to the custom-made process.
• Affordable price in its size and quality
• We have the mechanical data on following telescopes as of August 23 2022.

BORG : 150ED/125ED/107FL/100ED/90FL/76ED

Sky-watcher : EvoStar 150ED/120ED

Takahashi FS128

IStar 204

C8

• Specify us the accurately measured circumference data for the dew-shield if your scope is not listed above.