Sharpstar 150mm f/2.8 HNT Hyperbolic Newtonian Astrograph (Aluminum Tube)
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The Sharpstar 15028HNT-AL is a hyperbolic Newtonian reflector with a 150mm aperture and a fast f/2.8 focal ratio that supports a 44mm full frame image circle.
The primary mirror is made of Pyrex-like glass PZ33, which has a thermal expansion coefficient smaller than ordinary glass while the dielectric multilayer coating proviides a highly reflective 97%. The diameter of the secondary mirror minor axis is 70mm, enabling sufficient illumination for full-frame imaging. The corrector in the focuser adopts a triplet lens design, one of which is an ED glass, that corrects for coma and other aberrations.
Three sets of adjustment screws at the bottom of the optical tube enable the user to adjust the angle of the primary mirror further enhancing the structural stability and accuracy of the optical axis.
The 15028HNT-AL incorporates a robust and rigid CNC machined four vane secondary mirror spider which ensures beautiful diffraction spikes during astrophotography.
There is a finder base on the side of the lens tube, which provides additional mounting positions for a finder scope or other astronomical accessories.
15028HNT-AL's tube rings are sturdy and durable with enlarged hand screws allowing users to open and close the rings without additional tools.
15028HNT-AL's focuser is a dual-speed rack-and-pinion focuser with 20mm of travel and is compatible with most motorized focusers on the market. The focuser incorporates a camera rotator with a built-in triplet corrector and can successfully carry up to 3kg (6.6lbs).
The back focus of 15028HNT-AL is standard 55mm (from the M48 thread).
*The 15028HNT-AL focuser is shipped in a locked condition. Users should be sure to loosen the locking screws before initial use to avoid damaging the part.
Standard Losmandy-style 200mm dovetail plate and 200mm handle bar included.
15028HNT-AL is all-metal, with an aluminum tube and CNC machined parts.
Full Optical and Mechanical Testing and Quality Control - An Agena Exclusive!
Agena does much more than simply move the telescope boxes from Sharpstar to you. Each Sharpstar imaging Newtonian telescope at Agena undergoes a thorough physical, mechanical, and optical evaluation at our shop upon arrival - all at no extra cost to you.
Every telescope is inspected to ensure good cosmetics, collimation, smooth focuser operation, and to make sure all parts are included by the manufacturer. Most importantly, we also check each telescope using a rigorous three-point on-site optical evaluation consisting of the following optical bench tests to ensure that your telescope delivers excellent optical performance:
- Foucault Test: This knife-edge test is performed at the center of curvature of the primary mirror to evaluate the quality of the mirror's conic shape.
- Ronchi Test: We then perform a Ronchi grating test at the center of curvature at inside focus, at focus, and outside focus. This is a qualitative method to evaluate primary mirror smoothness and figure.
- Star test: Finally, we collimate the complete telescope and perform an autocollimation test with an artificial star to examine the overall system's image performance at the focus point.
This testing is performed and certified by a master optician to make sure each Sharpstar instrument sold by Agena has excellent optical performance before it ships.
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 glass)
- Corrector: Three-element air-spaced (including one ED glass)
- Minor axis of secondary mirror: 70mm
- Image circle: 44mm
- Field of view: 6 degrees
- Main tube material: Aluminum
- Main tube outer diameter: 193mm
- Main tube length: 443mm
- OTA weight: 4.8kg (10.5lbs)
- Gross weight (including tube ring and dovetail plate): 6kg (13.2lbs)
- Resolution: 0.77 arc second
- Limiting visual magnitude: 12.7
- Back-focus: 55mm
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free Contiguous US Shipping |
| Telescope Focal Length | 401 - 500mm |
| Hide Found a better Shipped Price on Frontend? | No |
The Sharpstar 15028HNT-AL is a hyperbolic Newtonian reflector with a 150mm aperture and a fast f/2.8 focal ratio that supports a 44mm full frame image circle.
The primary mirror is made of Pyrex-like glass PZ33, which has a thermal expansion coefficient smaller than ordinary glass while the dielectric multilayer coating proviides a highly reflective 97%. The diameter of the secondary mirror minor axis is 70mm, enabling sufficient illumination for full-frame imaging. The corrector in the focuser adopts a triplet lens design, one of which is an ED glass, that corrects for coma and other aberrations.
Three sets of adjustment screws at the bottom of the optical tube enable the user to adjust the angle of the primary mirror further enhancing the structural stability and accuracy of the optical axis.
The 15028HNT-AL incorporates a robust and rigid CNC machined four vane secondary mirror spider which ensures beautiful diffraction spikes during astrophotography.
There is a finder base on the side of the lens tube, which provides additional mounting positions for a finder scope or other astronomical accessories.
15028HNT-AL's tube rings are sturdy and durable with enlarged hand screws allowing users to open and close the rings without additional tools.
15028HNT-AL's focuser is a dual-speed rack-and-pinion focuser with 20mm of travel and is compatible with most motorized focusers on the market. The focuser incorporates a camera rotator with a built-in triplet corrector and can successfully carry up to 3kg (6.6lbs).
The back focus of 15028HNT-AL is standard 55mm (from the M48 thread).
*The 15028HNT-AL focuser is shipped in a locked condition. Users should be sure to loosen the locking screws before initial use to avoid damaging the part.
Standard Losmandy-style 200mm dovetail plate and 200mm handle bar included.
15028HNT-AL is all-metal, with an aluminum tube and CNC machined parts.
Full Optical and Mechanical Testing and Quality Control - An Agena Exclusive!
Agena does much more than simply move the telescope boxes from Sharpstar to you. Each Sharpstar imaging Newtonian telescope at Agena undergoes a thorough physical, mechanical, and optical evaluation at our shop upon arrival - all at no extra cost to you.
Every telescope is inspected to ensure good cosmetics, collimation, smooth focuser operation, and to make sure all parts are included by the manufacturer. Most importantly, we also check each telescope using a rigorous three-point on-site optical evaluation consisting of the following optical bench tests to ensure that your telescope delivers excellent optical performance:
- Foucault Test: This knife-edge test is performed at the center of curvature of the primary mirror to evaluate the quality of the mirror's conic shape.
- Ronchi Test: We then perform a Ronchi grating test at the center of curvature at inside focus, at focus, and outside focus. This is a qualitative method to evaluate primary mirror smoothness and figure.
- Star test: Finally, we collimate the complete telescope and perform an autocollimation test with an artificial star to examine the overall system's image performance at the focus point.
This testing is performed and certified by a master optician to make sure each Sharpstar instrument sold by Agena has excellent optical performance before it ships.
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 glass)
- Corrector: Three-element air-spaced (including one ED glass)
- Minor axis of secondary mirror: 70mm
- Image circle: 44mm
- Field of view: 6 degrees
- Main tube material: Aluminum
- Main tube outer diameter: 193mm
- Main tube length: 443mm
- OTA weight: 4.8kg (10.5lbs)
- Gross weight (including tube ring and dovetail plate): 6kg (13.2lbs)
- Resolution: 0.77 arc second
- Limiting visual magnitude: 12.7
- Back-focus: 55mm
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free Contiguous US Shipping |
| Telescope Focal Length | 401 - 500mm |
| Hide Found a better Shipped Price on Frontend? | No |
Sharpstar 150mm f/2.8 HNT Hyperbolic Newtonian Astrograph (Aluminum Tube) # 15028HNT-AL