Explore Scientific FCD100 127mm f/7.5 Triplet APO Refractor Telescope

Explore Scientific FCD100 127mm f/7.5 Triplet APO Refractor TelescopeThe Explore Scientific FCD100 127mm APO delivers the same premium HOYA FCD100 optics found in refractors costing $3,000$5,000, in a proven aluminum optical tube at a fraction of the price. This air spaced triplet design achieves 0. 91 arcsecond resolution with virtually zero chromatic aberration performance that Cloudy Nights reviewers have called "neck and neck" with an Astro Physics Starfire. At 952mm focal length and f 7. 5, it's equally at home on

The Explore Scientific FCD100 127mm APO delivers the same premium HOYA FCD100 optics found in refractors costing $3,000–$5,000, in a proven aluminum optical tube at a fraction of the price. This air-spaced triplet design achieves 0.91 arcsecond resolution with virtually zero chromatic aberration — performance that Cloudy Nights reviewers have called "neck and neck" with an Astro-Physics Starfire. At 952mm focal length and f/7.5, it's equally at home on planets and deep-sky targets.

Key Features

• HOYA FCD100 Extra-Low Dispersion Glass – FPL-53 equivalent optics virtually eliminate false color, delivering pinpoint stars and true-to-life colors in both visual and imaging use
• Air-Spaced Triplet APO Design – Three-element optical system achieves diffraction-limited performance with 0.91 arcsecond resolution and high contrast across the field
• Durable Aluminum Optical Tube – Classic white-finish aluminum construction provides a rigid, reliable platform for both permanent observatory setups and field use
• 2.5" Hexagonal Dual-Speed Focuser – Rock-solid rack-and-pinion design with 10:1 fine focus supports up to 10 lbs of imaging gear with zero flex or image shift
• EMD Enhanced Multi-Layer Coatings – Proprietary broadband coatings maximize light transmission and contrast for faint deep-sky targets
• Versatile f/7.5 Focal Ratio – Long enough for high-magnification planetary detail, yet pairs beautifully with the 0.7x reducer for faster deep-sky imaging at f/5.25
• Retractable Dew Shield – Blocks stray light and slows dew formation during extended sessions
• 99% Reflective 2" Diagonal Included – Premium dielectric diagonal maximizes light throughput right out of the box

Ideal For

• Serious visual observers stepping up from doublets or entry-level triplets who want pinpoint stars, jet-black backgrounds, and zero false color on planets and double stars
• Astrophotographers who need tight, round stars across the field and a focuser that won't flex under the weight of a dedicated astronomy camera, filter wheel, and auto-guider
• Observatory and backyard setups where the telescope lives on a permanent or semi-permanent mount — the aluminum tube's added weight is a non-issue when you're not hauling gear, and its rigidity is an asset
• Upgraders from 80–102mm APOs looking for a meaningful jump in aperture and resolution — the 127mm aperture collects 56% more light than a 102mm and delivers noticeably finer detail

Accessories & Compatibility

• Explore Scientific 3" Field Flattener & 0.7x Focal Reducer – Corrects field curvature and reduces focal length to f/5.25 for faster deep-sky imaging with sharp, flat stars edge-to-edge
• Explore Scientific 8x50 Illuminated Right Angle Polar Finder – Accurate polar alignment with an illuminated reticle for precise tracking during long exposures
• Explore Scientific EXOS2-GT Equatorial Mount – GoTo motorized mount with PMC-Eight system for automated object tracking and long-exposure astrophotography
• Explore Scientific Soft-Sided Telescope Case – Padded protection for safe transport to dark-sky sites

Looking for the lightweight option? The FCD100 127mm Carbon Fiber version shares the same optics and focuser in a carbon fiber tube that's 4 pounds lighter with superior thermal stability — ideal for portable setups and travel.

Note: A finder scope and carrying case are not included. The pre-installed 2N1 finder scope base accepts most standard finder scopes and guiding systems.