The Lunt Zoom Eyepiece # LS7-21ZE offers ideal magnifications for the standard focal lengths of Lunt H-alpha solar telescopes. It's an ideal 'first look' eyepiece that allows you to quickly view the Sun at a lower magnification, then zoom to higher magnification to see interesting details.


The focal length of this 1.25" eyepiece ranges from 7.2 mm to 21.5 mm with graded markings at focal lengths of 7.2mm, 10mm, 13.5mm, and 21.5mm. The power change ring on the eyepiece features a ribbed gripping surface that makes it easy to make small power changes between these ranges, even when wearing gloves.


The optics in the eyepiece consists of 7 multi-coated lens elements in 4 groups for clear, crisp images. The apparent field of view ranges from 40 degrees at 21.5mm to 60 degrees at 7.2mm. Eye relief is a comfortable 15mm and the barrel is threaded for standard 1.25" filters when the eyepiece is used for general non-solar observing.


While designed for solar observing with a Lunt solar telescope, this eyepiece can also be used for general terrestrial or night-time observing with a non-solar telescope. (Note: For safe solar observation, this eyepiece MUST be used with a solar telescope equipped with safe solar filters).


The Lunt Zoom Eyepiece is great little eyepiece at an affordable price.


Please Note: Zoom eyepieces will produce a ratting sound when shaken. This is due to the clearances required for moving parts of the zoom mechanism, and does not indicate defects or loose lenses. This sound is completely normal.