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  • 15mm optical path length
  • Telescope side T-2 internal thread
  • Focus side T-2 external thread
  • For eyepiece projection with shift/sliding focuser

T-2 Extension Tubes enable you to securely set or vary the spacing between T-2 components. The tubes are available in three lengths, 7.5mm, 15mm, and 40mm, and are provided with an internal T-2 thread at one end and an external T-2 thread at the opposite end. Full internal threading and blackening kills any stray light reflections.

T-2 Extension Tubes are used throughout the ASTRO T-2 System™ to provide proper spacing of system components. The Alan Gee Mark II Telecompressor may be configured in various ways that benefit from the ability to vary the spacing of the lens relative to camera or eyepiece. The extension tubes provide a secure way of varying projection ratios (eyepiece to camera separation), for the OPFA System (afocal and ocular projection), and the MPCC makes use of the T-2 Extension tubes to accurately locate and couple the coma corrector to eyepieces. You can use the extension tubes anywhere you need to precisely space and couple any of the T-2 components, in configurations of your own design.