BAADER PLANETARIUM HYPERION UNIVERSAL ZOOM MARK IV, 8-24MM EYEPIECE (1¼” / 2″)

Some of the special feature of this very high-quality zoom eyepiece include:

• connection to telescope – 2″ and 1.25″ barrels (the normal sizes with telescope focusers). Also suitable for all 1.25″ bino-viewers, and includes a 1 and 3/8″ spotting scope thread.
• camera side – M43 camera/video adapter thread for afocal and classic projection photography, allows the connection of most cameras.
• for visual use – includes three different eyecups that fit over the M43 thread: a large height-adjustable eyecup, a smaller rubber eyecup and a fold-down winged eyecup.
• safety kerfs instead of irritating safety grooves in the barrels
• eyepiece holster with belt loop – also attaches to tripod legs

Baader Phantom Group coating™ – this is a 7-layer broadband anti-reflection coating with extremely low residual reflection. The designation ‘Group’ indicates that the most effective anti-reflection layer system is worked out for each type of glass used in the respective eyepiece.

All these various antireflection coatings, on each type of glass surface, have then been optimized so that they are most effective where the human eye is at its most sensitive at night – i.e. at about 520nm, which is in the green region of the spectrum.

The best anti-reflection coatings appear almost colourless – this proves that the coating is functioning equally well over the entire visible spectrum. Phantom Group antireflection coatings are – depending on the type of glass – almost entirely colourless. In this way it is ensured that the least light is lost to the night-adapted eye and that no scattered light will interfere.

If you look directly at a coated lens (eyepiece or objective) and can see a strong green reflection, then it is not a Baader Phantom Group coating! An intense green reflection is indicative of a relatively low-tech coating technology and means that light is being wastefully reflected – i.e. lost – right in the useful spectral range between 500-550nm