Eyepiece Delta Optical Plossl 9mm 52° 1.25″

DeltaOptical Plossl 9mm 52° 1.25″ eyepiece

Looking for an eyepiece that reveals fine details on the lunar surface, planetary discs or dense globular clusters? The DeltaOptical Plossl 9mm eyepiece is a classic choice built on the proven four-element Plossl design, combining an affordable price with optical performance that satisfies even the more demanding observer. The short 9mm focal length delivers high magnification, which you will appreciate most when closely examining surface features or watching planetary phases.

Plossl optical design

The Plossl is a symmetric four-element system consisting of two achromatic doublets facing each other. This arrangement achieves excellent correction of both chromatic and spherical aberration across the entire field of view. The 52° apparent field of view is the standard for this class of eyepieces - it is not the widest view on the market, but it offers a comfortable compromise between overview and sharpness right to the edges.

Eye relief corresponds to the focal length of the eyepiece, which is a natural characteristic of short Plossl designs. Observers who wear glasses may find access to the full field of view slightly limited - this is something to keep in mind when choosing a short focal length eyepiece.

Universal 1.25″ barrel - compatible with most telescopes

The standard 1.25″ barrel diameter ensures universal compatibility with the vast majority of astronomical telescopes on the market - refractors, Newtonian reflectors and catadioptric systems (SCT, Maksutov). The 9mm focal length works particularly well with mid-sized telescopes with a focal length in the range of 700-1500mm, where it delivers magnification of approximately 80x to 170x. This is an ideal range for observing planetary details, lunar craters or Saturn's ring division under good atmospheric conditions.

Who is this eyepiece for?

The DeltaOptical Plossl 9mm is an excellent choice for:

• Beginners looking for a reliable high-magnification eyepiece to complement a wide-angle eyepiece
• More experienced observers building an economical set of eyepieces with varying focal lengths
• Anyone who needs a backup eyepiece for field use, without risking more expensive optics

DeltaOptical - quality optics at an accessible price

DeltaOptical is a brand with a clear philosophy - bringing quality optics within reach of a wide audience of astronomy and nature observation enthusiasts. The DeltaOptical Plossl eyepiece range features a proven optical design with carefully applied anti-reflection coatings on all lens surfaces, minimising unwanted reflections and ensuring good light transmission.

For anyone building up an eyepiece collection step by step and wanting the assurance that every piece will perform reliably night after night, DeltaOptical eyepiece series represent a sensible and trustworthy choice.

Technical specifications