Eyepiece TS Optics Ploessl 4mm 52° 1.25″

TS Optics Plössl 4mm eyepiece - 52° field of view, 1.25″

Are you looking for a reliable eyepiece that will reveal fine details on the Moon, planets, and bright deep-sky objects? The TS Optics Plössl 4mm eyepiece is a classic, well-proven design with modern optical coatings that delivers a sharp and high-contrast image even at high magnification. With a focal length of just 4mm and a standard 1.25″ barrel, this eyepiece is an excellent tool for anyone who wants to get the most out of their telescope.

Optical design and coatings

The Plössl design uses a four-element optical system built from two symmetrically arranged doublets. This construction provides excellent correction of chromatic aberration - false color is reduced to a practically negligible level. Fully multi-coated (FMC) optics on all air-to-glass surfaces significantly increase light transmission and image contrast, which you will especially appreciate when observing fine planetary details or dark cloud bands on Jupiter. All lenses are made of glass, not plastic, which improves both optical performance and long-term durability.

Build quality and compatibility

The eyepiece body is made of metal, not plastic, which ensures precise alignment of the optics and resistance to everyday use. A soft rubber eyecup effectively blocks stray light and also protects the eye and eyeglasses of the observer. The 1.25″ barrel is the standard format compatible with the vast majority of telescopes available on the market, so installation is quick and straightforward.

Planetary and lunar observation

High-magnification lunar and planetary observation is the main strength of this eyepiece. The 4mm focal length combined with the 52° apparent field of view provides a comfortable view even at high magnifications - with a telescope of 1000mm focal length you will reach a magnification of 250×. The 52° field of view still ensures that you will not feel like you are looking through a keyhole. Thanks to the low-distortion four-element optics, the eyepiece is also suitable for projection photography of planets and the Moon.

Plössl versus simpler designs

Using a Plössl-type eyepiece is noticeably better compared to simpler designs such as Kellner - improved aberration correction, higher contrast, and a flatter image across the entire field of view make this model a versatile choice for any astronomy kit bag.

Who is this eyepiece for?

The TS Optics Plössl 4mm is an excellent choice for both beginners and more experienced astronomers who are looking for a reliable, optically high-quality eyepiece at a reasonable price. The combination of a metal body, glass optics with FMC coatings, and the classic Plössl design delivers performance that clearly surpasses cheaper alternatives. Whether you are observing craters on the Moon, the rings of Saturn, or the cloud bands of Jupiter, this eyepiece will not disappoint.

Technical specifications