• The Pleiades 181's advanced optics set it apart from similar-sized optical tubes, with a 7-element, temperature-compensated lens system that minimizes thermal distortion and maintains rock-solid image clarity throughout the imaging session, preventing blurring and focus shifts during long exposures.
• With a minimum Strehl ratio of 0.96, the optical tube offers highly refined optics, delivering images with exceptional contrast and clarity. A Strehl ratio above 0.8 is considered excellent, making this telescope ideal for capturing detailed images of distant objects like galaxies, nebulae, and star clusters.
• The telescope is optimized for medium format cameras, which offer superior resolution, light-gathering power, and dynamic range compared to standard sensors. This makes it perfect for capturing fine details of the cosmos, with included M68, M54, and M48 adapters for compatibility with a wide range of medium format cameras.
• Despite its large size, the Pleiades 181 features a steering wheel for easy rotation, making it more convenient to adjust the telescope when necessary.
• The Pleiades 181's optical tube weighs just 33.07 lbs (41.23 lbs fully equipped with rings, dovetail, and saddle), making it relatively lightweight for a refractor of its size, ensuring manageable portability.
• The optical tube length ranges from 1231mm (when the dew shield is retracted) to 1496mm (when extended), offering flexibility in setup.
• Equipped with a 4.1" rack and pinion focuser, the Pleiades 181 is also compatible with the ZWO EAF for automated focusing.

The optical performance of the Pleiades 181’s advanced optics stand out as a major distinction compared to other similar sized optical tubes. Its 7 element and temperature-compensated lens system is designed to significantly keep thermal distortion at bay, thus keeping image clarity rock solid as temperature changes throughout the imaging session. In essence, this helps remove blurring and shifts in focus that would otherwise occur the long exposures become.

The Pleiades 181 boasts a minimum Strehl ratio of 0.96, meaning its optics are highly refined and produce images with very high contrast and clarity. A Strehl ratio above 0.8 is typically considered excellent for high-quality imaging, and with a ratio of 0.96, this telescope delivers superior optical performance that’s ideal for capturing intricate details of distant objects like galaxies, nebulae, and star clusters. Coupled with high resolution cameras, this in turn results in fantastic exposures of cosmic structures and events!

The Pleiades 181’s optimization for medium format cameras is a significant factor that elevates it as an essential tool for serious astrophotographers. Medium format cameras, with their larger sensors compared to standard full frame or crop sensors, offer a number of advantages in astrophotography, notably increased resolution, better light-gathering capabilities, and a broader dynamic range. These are must have qualities for superb detail of the cosmos where every pixel counts! In the case of viewing deep sky, the wide field of views are splendid with sensors of this size. With M68, M54, and M48 adapters included, many varieties of Medium Format cameras can be used.

Due to the large size for a refractor, William Optics implemented a Steering Wheel for users to rotate the scope. This makes it easer to move if necessary.

Notwithstanding its large 181mm aperture, the William Optics Pleiades 181 is designed to simultaneously stay lightweight for the size; weighing just 33.07 lbs for the optical tube (OTA) and 41.23 lbs when fully equipped with rings, dovetail, and saddle. While still heavier than most refractors that are smaller, it is still manageable enough for relatively easy transport if needed. With dew shield retracted and extended, the OTA length if 1231-1496mm.

The Pleiades 181 comes with a 4.1" Rack and Pinion Focuser. It is compatible with the ZWO EAF.