Astronomer UHC-E filter in a 2 "/ 50.8 mm housing.
Astronomik UHC-E is a budget filter for observing emission nebulae and comets under a sky polluted by light. Recommended especially for small telescopes. It blocks the wavelengths typical of street lighting, as well as the lighting of the atmosphere.
The UHC-E filter is characterized by a half width of 45 nm, which allows it to pass a spectral line of carbon. This opens the possibility of observing comets.
• nebulous filter for observation in the city
• anti-light pollution filter for small and medium telescopes - transmits more light than UHC filters
• allows observation of comets
• improves the visibility of clouds on Jupiter
• facilitates the separation of double stars
• good for photography under urban sky using SLR cameras and other cameras
• visual observations under dark sky: good, UHC seems to be a better choice
• visual observations under the urban sky: good for telescopes with an aperture of up to 125 mm
• film photography: good for very long exposure times
• CCD photography: good when used with an additional IR filter
• unmodified mirror photography: good, color balance is almost perfect
• photo of a reflex camera modified for astrophotography: good, color balance is almost perfect
• webcam / video cameras for planetary photography: not applicable
• webcam / video cameras for photos of nebular objects: very good if light pollution at the observation site is a big problem
• FWHM = 45 nm
• maximum transmission 94%
• permeability range from 480 nm to 525 nm and from 645 nm onwards
• diffraction-limited accuracy
• parchocal with other Astronomic filters
• thickness: 1 mm
• resistant to moisture, scratch, does not age
The filter is especially recommended for telescopes with a diameter of up to 5 "/ 125 mm For larger telescopes, the UHC filter will provide a higher contrast improvement, and telescope holders over 8" / 200 mm can test O-III filters when observing certain nebulae.