2" UHC-L filter Beta model 2961563 Ultra-L-Booster for astronomical telescopes

2" UHC-L filter Beta model 2961563 Ultra-L-Booster for astronomical telescopes is an optical nebula filter designed for use with 2" eyepieces and camera adapters. Housed in a 2-inch cell, this UHC-L (Ultra-High Contrast) filter selectively transmits prominent emission wavelengths while suppressing much of the background skyglow. The result is improved contrast and enhanced visibility of emission nebulae and other deep-sky objects under both dark and light-polluted skies. The filter is suitable for visual observing and for imaging workflows where a 2" interface is required.

Advantages

The Beta Ultra-L-Booster increases contrast by passing targeted nebular emission lines and attenuating unwanted continuum light, which helps to reveal faint nebular structures. Its 2" mounting cell provides secure, standardized attachment to eyepieces and adapters compatible with 2" accessories. The optical coating is engineered for consistent transmission at the specified wavelengths, supporting both visual use and astrophotography without introducing significant color cast when used as intended.

Suitable for

• Visual observation of emission nebulae through telescopes with 2" eyepieces
• Imaging emission nebulae and other deep-sky objects using 2" camera adapters
• Astronomical observing from suburban or light-polluted locations to increase contrast
• Use in refractors, reflectors and SCTs that accept 2" filter cells

Key specifications

• Filter type: UHC-L (Ultra-High Contrast) nebula filter
• Mount diameter: 2-inch cell for standard 2" accessories
• Optical purpose: contrast enhancement of emission nebulae and suppression of skyglow
• Compatible use: visual observing and imaging with 2" eyepieces or adapters

How to use

Install the filter into the 2" focuser, eyepiece or camera adapter according to the telescope's accessory mounting procedure. For visual observing, insert the 2" eyepiece with the filter in place and allow a short period for the eye to adapt to the new contrast. For imaging, place the filter in the optical train between the telescope and camera using the appropriate 2" adapter and focus carefully; some refocusing may be required after fitting the filter. Use standard alignment and focusing procedures for your telescope, and avoid touching the optical surface to prevent fingerprints or smudges.

Usage recommendations

Best results are achieved when using the filter on emission-line targets such as H II regions, planetary nebulae and supernova remnants. From light-polluted locations the filter improves contrast, though longer exposures or stacking may still be necessary for faint details during imaging. Clean the filter only with blower, lens paper or a microfiber cloth and appropriate optical cleaning fluid when required, and store it in a protective case when not in use.