DeltaOptical/GSO Plössl 12mm 52° 1.25″ eyepiece
Looking for an eyepiece that handles everything from the Moon and planets to nebulae - without sacrificing sharpness or contrast? The DeltaOptical/GSO Plössl 12mm is a classic choice with a proven optical design, trusted by beginners and experienced astronomers worldwide. Its 12mm focal length delivers a comfortable medium magnification that is ideal for detailed planetary observation as well as viewing bright deep-sky objects.
Optical quality you can see
The Plössl eyepiece with fully multi-coated anti-reflection coatings on all optical surfaces significantly reduces unwanted reflections and light scatter, which would otherwise lower contrast and create ghost images. The result is a sharp, bright and vivid image free from chromatic and spherical aberrations. The four-element symmetric Plössl design ensures uniform sharpness across the entire 52° field of view, so the edges of the image are just as clean as the center - something especially appreciated when observing extended objects.
Versatile 12mm focal length for a wide range of targets
The standard 1.25″ barrel diameter ensures compatibility with the vast majority of telescopes on the market - from refractors and reflectors to catadioptric systems. The 12mm focal length is extremely versatile in practical use: combined with a telescope of 600-1200mm focal length, it delivers magnifications in the range of 50x to 100x. This is the ideal range for observing the Moon, Saturn with its rings, Jupiter's cloud bands or double stars. At the same time, the eyepiece is sufficiently light-efficient for viewing nebulae and star clusters under a dark sky.
The Plössl 12mm is one of the most widely used eyepieces in astronomical practice precisely because it sits at the boundary between medium and higher magnification, handling a broad spectrum of objects without compromise. Whether you are just beginning your journey in astronomy or adding a reliable mid-range piece to your eyepiece collection, this focal length is one that should not be missing from your kit.
About DeltaOptical/GSO - quality and value
DeltaOptical/GSO eyepieces combine a proven optical design with rigorous manufacturing quality control. GSO is a renowned Taiwanese manufacturer of astronomical optics with a long-standing tradition, whose products are sold under various brand names worldwide and are known for their excellent performance-to-price ratio. The multi-layer anti-reflection coatings from this manufacturer are not just a marketing promise - they translate into genuinely higher contrast and image clarity that you will notice at every observing session. If you are looking for a reliable eyepiece without unnecessary compromises at a reasonable price, the DeltaOptical/GSO Plössl 12mm is a choice you will not regret.
Key specifications
| Parameter |
Value |
| Focal length |
12mm |
| Apparent field of view |
52° |
| Barrel diameter |
1.25″ |
| Optical design |
Plössl (4-element symmetric) |
| Coatings |
Fully multi-coated (FMC) |
| Compatible telescopes |
Refractors, reflectors, catadioptric systems |
| Recommended telescope focal length |
600-1200mm |
| Resulting magnification range |
50x - 100x |
