Brand and Model: | Guan Shen Optics 42mm |
Price ($USD): | $59.00 |
Type: | Misc Wide Angle |
Focal Length: | 42 mm |
Barrel Size: | 2 |
Apparent FOV: | 65.0 degrees |
Field Stop Dia.: | 47.0 mm |
Eye Relief: | 15 mm |
Elements: | 5 |
Weight (lbs): | 320g |
Description: | GSO eyepieces offer a great value for money. They feature a modern optical design, allowing for the use with "fast" focal ratio telescopes down to f/5.
-fully multicoated for best possible contrast and transmission Mechanical features metal body with rubber grip and soft rubber eyecups against stray light Image quality crisp and contrasty images without distortion near the edge. Many eyepieces with larger apparent fields of view have quite some noticable distortion towards the edge of the field of view, thus apparently reaching wider fields without changing the actual field of view. TS WA eyepieces do not use this trick. Usable with: You can use these eyepieces with any telescopes with a focal ratio of f/5 or longer. Please keep in mind that the exit pupil does not get too large with the long focal length TS WA eyepieces, though. (For example, at f/5 you may well use the GSO 32, but the GSO 42 and 50 will render a not-quite-useful exit pupil of 8.4mm or 10mm, respectively. The exit pupil should never grow bigger than your own eyes' pupils can, otherwise you will waste light.) |