The UHC-E - Economy UHC Filter - 1.25-Inch Round Mounted by Astronomik:
Astronomik's UHC-E (Ultra High Contrast - Economy) filter is THE budget filter for deep-sky observation of emission nebulae and comets under light polluted skies. It is particularly suitable for small scopes. The UHC-E Filter increases contrast of emission nebulae and comets and blocks the light of typical streetlights as well as airglow. It is best suited for telescopes up to 5-inch/ 125 mm.
The Astronomik UHC-E filter provides a FWHM of 45 nm and blocks the light of typical streetlights (e.g. sodium and mercury vapor) as well as airglow. Thus it increases contrast between your target and the night sky. The contrast enhancement is less than that of the Astronomik UHC filter, but at the same time the transmitted amount of starlight is greater. It's therefore better suited to smaller telescopes. As the UHC-E filter passes a spectral line of Carbon (due to the higher FWHM) it opens up the possibility of comet observation, observation of Jupiter's clouds, easier resolution of Double Stars, and photography under light-polluted skies with DSLRs and other cameras.
If you use a telescope with an aperture larger than 5-inch, we suggest the use of the standard UHC-filter because of its greater contrast enhancement capabilities. If you use a telescope larger than 8-inch, you can try the Astronomik OIII filter for even better results when observing specific nebulae.
Astronomik 1.25" Economy UHC Filter Features:
- Maximum transmission of 94-percent
- Full width at half maximum 45 nm
- Transmission range 480 nm to 525 nm and 645 nm+
- Parfocal with other Astronomik filters
- Glass thickness: 1 mm
- Completely resistant against high humidity, scratches and aging effects
- Diffraction limited, the filter will not reduce the optical performance of your telescope!
- Astronomik filters are delivered in a high-quality, long lasting, filter box.
OPT Product Number: AK-UHCE-1