TS-Optics Expanse 17 mm 70° Wide-Angle Eyepiece with 1.25" and 2" connection

TS-Optics Redline Expanse - 70° Wide-Angle Eyepiece with ED Optics

You may have experienced this: You point your telescope at an interesting object, but the image is not quite as sharp or high-contrast as you expected. Often, this is not due to the telescope itself, but to the eyepiece, as it plays a decisive role in the quality of your observation. With TS-Optics Redline Expanse eyepieces, you willl experience a high-contrast, detailed image. Blackened lens edges and an integrated ED element ensure a particularly clear and brilliant image. The 70° wide-angle field of view opens up an impressively large section of the sky.

ED optics high contrast for planets and deep-sky objects

When looking through a Redline eyepiece, the brilliance, clarity, and color depth are immediately apparent. The ED element reduces chromatic aberration and ensures high sharpness and strong contrast. The strength of this optics is particularly evident when observing planets: on Jupiter, fine details become visible, with cloud bands, swirling structures, and subtle color shades standing out clearly. At the same time, deep-sky objects also benefit from the clear and high-contrast image.

70° wide-angle observe like in a movie theater

With a 70° field of view, you experience the sky with exceptional intensity. Instead of a narrow tunnel view, a wide field of the sky opens up, allowing you to fully capture expansive objects. This field of view also corresponds to a physiologically comfortable range for the human eye. You observe in a relaxed manner and can enjoy the image without strain.

Long eye relief comfortable viewing

With a comfortable eye relief of 20 mm, every eyepiece in this series offers a particularly pleasant viewing experience. Even eyeglass wearers can use the full field of view without having to remove their glasses. Especially for those with astigmatism, it is even recommended to keep your glasses on to obtain the sharpest possible image.

Astrophotography made easy


Located beneath the eyecup is an M43 thread that allows for astrophotography directly through the eyepiece. With a compatible M43-to-T2 adapter, DSLR or compact cameras can be easily attached. This enables you to capture exciting images, such as of planets or the Moon. This feature is rarely found in eyepiece series of this class. The appropriate adapter is linked in the recommended accessories section.



1.25" and 2" barrel for maximum flexibility

The TS-Optics Redline Expanse eyepieces feature a 1.25" and a 2" barrel. This allows these eyepieces to be used with almost all standard telescopes. Only the 22 mm Expanse can be used exclusively on 2" focusers.

An eyepiece series for a wide range of magnifications

The TS-Optics Redline series includes the following focal lengths:
22 mm, 17 mm, 13 mm, 8 mm, 5 mm, 3.5 mm
This covers a wide range of magnifications, from wide-field deep-sky observations to high planetary magnifications. Another advantage: The eyepieces in this series are nearly parfocal, so refocusing is rarely necessary when switching between them.

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