Explore Scientific ED152 Triplet in Carbon Fiber

The ED152 CF: A 152mm f/8 APO for Advanced Imaging and Visual Astronomy

Designed as a flagship instrument, the ED152 Carbon Fiber is a professional-grade apochromatic refractor for the serious astronomer. Its 152mm (6") objective and f/8 focal ratio strike a critical balance, offering high magnification for planetary detail while maintaining a large enough image scale for many deep-sky targets. This is an instrument built for resolving fine details, from the Cassini Division in Saturn's rings to structure in bright nebulae.

The carbon fiber tube keeps the overall weight to just 20.5 lbs, making it remarkably portable for a telescope in this class. This also enables use with lighter equatorial mounts like the Losmandy G11 PMC-Eight, making the ED152 a viable option for both backyard observatories and dark-sky expeditions.

Air-Spaced Triplet Optics: HOYA FCD1 Glass for Apochromatic Correction

At the heart of the ED152 is an air-spaced triplet objective lens, the hallmark of a true apochromat (APO). This design uses three matched lenses, separated by a thin layer of air, to bring different wavelengths of light to a common focus. The result is crisp, color-corrected, high-contrast views across the field, without the purple fringing (chromatic aberration) common in simpler refractor designs.

To achieve this level of color correction, one of the three elements is made from genuine HOYA FCD1, a premium extra-low dispersion (ED) glass. This specific material has optical properties that allow for exceptional control over the light spectrum, so bright stars show little false color. This high-contrast, color-pure image is essential for discerning subtle details on planets and capturing accurate star colors in astrophotography.

The Power of 152mm: f/8 Focal Ratio and 125% More Light Than a 102mm

Aperture is the single most important factor in a telescope's ability to resolve fine detail and capture faint objects. The 152mm objective of the ED152 provides a significant jump in light-gathering power over smaller refractors. Compared to a 102mm model, the ED152 collects 125% more light, and 44% more than a 127mm refractor.

This light-gathering advantage translates directly to brighter images and shorter exposure times. Visually, you can resolve fainter stars in globular clusters like the Hercules Cluster (M13). For imagers, it means capturing more detail in the spiral arms of galaxies or the faint, extended nebulosity around targets like the Pleiades (M45) in less time.

Imaging-Grade Mechanics: The 3.3" Dual-Speed Focuser

The ED152 is equipped with a 3.3" dual-speed focuser (Explore Scientific's item code TED15208CF-HEX33 and price list give the 3.3" size). A large focuser leaves a wide opening for 2" accessories and camera adapters at the back of a long-focus refractor.

The dual-speed mechanism allows for both coarse and fine adjustments, making it easy to quickly find the general focal point and then dial in critical focus with precision. This fine control is indispensable for high-resolution planetary imaging and ensuring pinpoint stars in long-exposure deep-sky photography.

Carbon Fiber Construction: A 20.5 lb, 1041mm Optical Tube

A six-inch refractor is typically a heavy, cumbersome instrument, but the ED152's carbon fiber tube brings its weight down to a manageable 20.5 lbs. The retracted tube length is 1041mm, making it surprisingly transportable for its aperture class. The lower weight enables use with lighter equatorial mounts like the Losmandy G11 PMC-Eight.

Visual Observing with the ED152: The Included 2" Dielectric Diagonal

For visual observers, the ED152 includes a high-quality 2" dielectric diagonal with 99% reflectivity. This essential accessory ensures that the maximum amount of light from the objective reaches your eyepiece, preserving the brightness and contrast of the image.

The 2" barrel allows you to take full advantage of wide-field 2" eyepieces, the widest views this 1216mm telescope can give, for sweeping through the rich star fields of the Milky Way. A 1.25" adapter is also included, providing compatibility with the full range of standard eyepieces for high-power planetary and lunar observation.

Astrophotography with the ED152: A Stable Platform for Deep-Sky Imaging

The combination of apochromatic optics, a stable carbon fiber tube, and a heavy-duty 3.3" focuser makes the ED152 a formidable imaging platform. The 1216mm focal length provides excellent image scale for capturing detail in medium-sized to small galaxies and planetary nebulae. The f/8 focal ratio is also forgiving on eyepiece selection.

While the native optical system is highly corrected, astrophotographers using larger sensors will typically pair the telescope with a field flattener or reducer/flattener, which corrects the field curvature of a refractor toward the corners of the image. There is no dedicated corrector for the ED152 in the material we have.

Mounting the 20.5 lb ED152: Portability and Stability Considerations

While the 20.5 lb optical tube weight is exceptionally low for a 6-inch refractor, it still requires a stable, high-quality equatorial mount for optimal performance. The Explore Scientific Losmandy G11 PMC-Eight is an example of the lighter equatorial mounts the carbon fiber tube allows. For long-exposure astrophotography, add the camera and accessories and keep the total well within the mount's imaging capacity.

The reduced weight of the carbon fiber version not only widens the range of compatible mounts but also makes setup and transport easier. The 2026 catalog lists Vixen or Losmandy mounting for the ED152; check which dovetail your mount saddle takes.