Sharpstar HNT Series reflectors

Tuesday, January 14, 2025

Written By

Richard Harris is the founder and editor-in-chief of ScopeTrader, with over 40 years of experience in observational astronomy and astrophotography. He serves as director of the Ozark Hills Observatory, where his research and imagery have been featured in scientific textbooks, academic publications, and NASA-affiliated planetariums. Among his theoretical contributions is a cosmological proposition known as The Harris Paradox, which explores deep-field observational symmetry and time-invariant...

More articles by Richard Harris →

At a Glance The Sharpstar HNT Series reflectors, T13028HNT-AL and T15028HNT-AL, have been released. These hyperbolic Newtonian reflectors feature 130mm and 150mm apertures and a very fast F2.8 focal ratio in an aluminum tube version.

The new Sharpstar HNT Series reflectors T15028HNT-AL and T13028HNT-AL offer fast f/2.8 focal ratios, precise imaging capabilities, and practical design elements like built-in correctors and CNC-machined components. This release outlines their features and benefits for both enthusiasts and experienced users looking to improve their astrophotography setups.

The HNT Series T13028HNT-AL reflector stands out as a compact hyperbolic Newtonian reflector with a 130mm aperture and a fast f/2.8 focal ratio. Its lightweight aluminum tube and CNC-machined components ensure durability and portability. The primary mirror's 97% reflectivity and a 44mm full-frame image circle make it ideal for capturing detailed deep-sky images. Enhanced structural stability and a redesigned secondary mirror bracket ensure precise optical alignment and crisp diffraction spikes.

New Sharpstar HNT Series reflectors: 13028HNT-AL 15028HNT-AL

Focusing on stability and ease of use, the T13028HNT-AL features a dual-speed rack-and-pinion focuser that supports up to 3kg, with a built-in doublet corrector for aberration correction. Additional accessories, such as a Vixen-style dovetail plate and a finder base, enhance versatility. This model is a reliable choice for astrophotographers seeking precision and convenience.

Sharpstar HNT Series T13028HNT-AL specifications

Aperture Size: 130mm
Focal Length: 364mm
Focal Ratio: f/2.8
Primary Mirror Type: Hyperbolic reflective mirror
Primary Mirror Material: PZ33 (similar to Pyrex)
Corrector: Doublet lens, one ED glass element
Secondary Mirror Minor Axis: 65mm
Image Circle: 44mm
Field of View: 6.9 degrees
Main Tube Material: Aluminum
Main Tube Outer Diameter: 174mm
Main Tube Length: 400mm
OTA Weight: 3.8kg
Gross Weight: 4.8kg (including tube ring and dovetail plate)
Resolution: 0.89 arcseconds
Limiting Visual Magnitude: 12.3
Back Focus: 55mm
Dovetail Plate: Vixen-style, 290mm

T13028HNT-AL key features

The T13028HNT-AL excels in portability and precision with its compact design and 130mm aperture. Its highly reflective primary mirror and integrated corrector deliver excellent image clarity across a full-frame sensor. This model’s stability-focused design includes a CNC-machined secondary mirror bracket and a dual-speed focuser capable of supporting heavy imaging equipment.

Additional features, such as the Vixen-style dovetail plate, a finder base, and user-friendly adjustments for mirror alignment, make the T13028HNT-AL an accessible yet powerful tool for astrophotographers at any skill level. Its lightweight build and all-metal construction ensure long-term durability and reliability.

Sharpstar HNT Series T15028HNT-AL reflector

The T15028HNT-AL offers a step up with a 150mm aperture and the same fast f/2.8 focal ratio. Its Pyrex-alike PZ33 primary mirror delivers exceptional imaging performance, supported by a 44mm full-frame image circle and 97% reflectivity. Like its smaller counterpart, it features a CNC-machined secondary mirror bracket for stable alignment and sharp diffraction spikes.

Equipped with a dual-speed focuser, the T15028HNT-AL includes a built-in triplet corrector, ensuring superior aberration correction. The Losmandy-style dovetail plate and additional finder base enhance mounting options, while the robust aluminum construction ensures long-lasting performance. This model is tailored for advanced users seeking enhanced imaging capabilities.

Sharpstar HNT Series T15028HNT-AL specifications

Aperture Size: 150mm
Focal Length: 420mm
Focal Ratio: f/2.8
Primary Mirror Type: Hyperbolic reflective mirror
Primary Mirror Material: PZ33 (similar to Pyrex)
Corrector: Triplet lens, one ED glass element
Secondary Mirror Minor Axis: 70mm
Image Circle: 44mm
Main Tube Material: Aluminum
OTA Weight: ~4.8kg
Back Focus: 55mm
Dovetail Plate: Losmandy-style, 200mm

T15028HNT-AL key features

The T15028HNT-AL builds on the strengths of its smaller sibling, offering a larger 150mm aperture for greater light-gathering power. Its advanced triplet corrector ensures exceptional aberration correction, while the CNC-machined components guarantee precise alignment and stability.

Tailored for demanding imaging tasks, the T15028HNT-AL supports heavier accessories with its Losmandy-style dovetail plate and robust focuser. With its all-metal construction and thoughtful design, this model is perfect for advanced astrophotographers aiming to capture detailed and vibrant deep-sky images.