This 1/2" extension from Astro-Physics is a more robust version of T-thread extension tubes. It is fitted with 48 mm threads at both ends (male and female), rather than the smaller 42 mm threads. The internal light baffles are coated in a flat-black paint to avoid any unsightly reflections. You can use more than one in order to increase spacing distance and/or telecompression in 1/2" (12.7 mm) increments. This type of extension is often referred to as a "barrel extension" when threaded on to eyepiece barrels. Has a net spacing distance of 0.5" (12.7 mm).
- Since clear aperture is 44.5 mm (1.75"), it is designed to screw onto the 2" secure-grip nosepiece (AP16T) or any 2" nosepiece with 48 mm threads that is designed for CCD cameras
- Spacer for the 0.67 CCD Telecompressor (CCDT67) to achieve precise and/or additional telecompression. It also moves the CCDT67 further into the optical path, requiring less focuser in-travel
- Use with 1.25" adapter (ADA125) when using 2" filters and you need more space for long barrel eyepieces, to prevent striking the filter
- Extends the eyepiece barrel length of 1.25" / 2" eyepieces for use with 2" filters
- Use with advanced convertible Barlow (BARADV) in front of the MaxBright Diagonal (PMDMAX) for increased magnification
- Use with parfocal rings to accommodate eyepiece parfocality
- Facilitates focus with short focuser-travel systems like Newtonians