The 25 mm Starguider ED eyepiece is a perfect eyepiece for small magnifications (depending on the telescope), and thus the zooms most frequently used, both for preliminary observation of planetary objects and, above all, for observation of subtleties in gas nebulae. It is structurally constructed of six lenses in four groups, including two ED elements (low dispersion). Thanks to this, it allows for high contrast, excellent fidelity of color reproduction and extremely low levels of astigmatism and distortion, even in a short focal length telescope.
For example, in the William Optics ZenithStar 66 F / 5.9 apochromate, a magnification of 15.5x, "binocular," at which we rediscover the observation of the Pleiades and other large half-stars. In a 200 mm (8 ") f / 10 catadiopttrial telescope we get a magnification of 80x with a 0.75 ° field of view, appropriate for observing subtle details around the terminator on the moon or dense planetary nebulae and globular clusters.
The magnification that is obtained with this eyepiece is used every observation night, regardless of seeing.
In addition, the eyepiece is characterized by a 15 mm offset of the eye relief , which in combination with the retractable eyecup makes the eyepiece also suitable for people wearing prescription goggles.
An own field of view equal to 60 ° allows for easier finding and keeping the observed object in view.
StarGuider ED goggles are also known under the earlier trade name BST ED and Paradigm Dual ED. Read the review on CloudyNights.com
| • Focal length: || 25 mm |
| • Field of view: || 60 |
| • Distance of the exit pupil: || 15 mm |
| • Diameter of binding: || 1.25 inches |
| • Anti-reflective layers: || FMC |
| • Number of optical elements || 6 lenses in 4 groups, including 2 of ED glass |
| • Weight: || 205 g |