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Black cylindrical M68 extension tube, 20mm long

Baader Planetarium

Baader Planetarium M68 Extension Tube 20mm

SKU CH-ZH8K-J1ZMD

Adds 20mm of back-focus adjustment with M68 threads for precise telescope and camera alignment

  • Adds 20 mm for precise back-focus adjustment
  • M68 threads integrate with wide accessory range
  • High-grade construction ensures lasting stability
  • Precision machining minimises optical aberrations
  • Black plastic body withstands frequent field use

Precision M68 Extension Tube

The Baader Planetarium M68 Extension Tube adds 20mm of spacing to fine-tune back focus on telescopes and camera lenses with M68 threads. It suits astrophotographers and macro photographers who need precise optical alignment for critical imaging work.

Sustained Optical Performance

The high-grade black plastic body maintains rigid alignment under continuous use, preventing flex that could introduce aberrations during long exposures. Its robust construction preserves the integrity of the lens-to-camera connection across repeated observing sessions.

Verify Thread Compatibility

Confirm that your telescope, camera adapter, or lens accessory uses the M68 thread standard before ordering. This tube only fits equipment with matching 68mm threads and cannot bridge different thread sizes or bayonet mounts.

Highlights

  • Adds 20 mm for precise back-focus adjustment
  • M68 threads integrate with wide accessory range
  • High-grade construction ensures lasting stability
  • Precision machining minimises optical aberrations
  • Black plastic body withstands frequent field use

Specifications

No published specifications for this item yet.

Questions about this item

How much extra back-focus length does the 20 mm M68 tube add to the optical train?

The tube adds exactly 20 mm of extension, allowing precise back-focus adjustment for sharper imaging with M68-threaded telescopes and accessories.

Which thread standard must my telescope or camera adapter already use to attach this tube?

Your equipment needs M68 threads on both mating surfaces; the tube has male and female M68 ends that screw directly into that thread size.

Will the black plastic body of this 20 mm spacer maintain alignment when stacked with older metal M68 components?

Yes, the precision-machined plastic tube is built for rigid, repeatable alignment and mates securely with existing M68 metal parts without introducing tilt.

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