About this product
Part Number: 15028HNT
Optical Bench Test
All SharpStar telescopes are tested in the UK on an optical bench.
This ensures you can be confident your telescope will, from the outset, have well figured optics, negligible false colour and spherical aberration, and no astigmatism (the bane of any optical system!). Star shapes will be round, not triangular, oval or egg-shaped!
SharpStar 15028HNT Hyperbolic Newtonian Astrograph
The SharpStar 15028HNT Hyperbolic Newtonian Astrograph is a compact 150mm f/2.8 reflector using an innovative optical design and multiple precision elements to provide a 44mm image circle that fills 36mmx44mm full-frame sensors with an ultra wide 6 degree field of view. This is the ideal instrument for astrophotographers looking to capture wide field deep sky targets with a super fast optical system.
The fast f/2.8 focal ratio arises from the integration of a 150mm hyperbolic primary mirror with enhanced aluminium coatings with 96% reflectivity. This type of mirror delivers reduced aberration and field curvature at the edge of the wide field of view. The large 70mm secondary mirror passes light through a three-element corrector lens to deliver a crisp, sharp, and bright image over the entire 44mm image circle with minimal chromatic aberration and outstanding field flatness.
The SharpStar 15028HNT is engineered and constructed to be durable for field use, yet portable and lightweight enough to make it easy to mount and handle. The scope uses an 18"-long carbon fibre tube and CNC aluminium fittings for a precision fit and finish. The 2.5” dual-speed rack and pinion focuser is capable of handling larger cameras and accessories without slipping. The focuser also comes with a 1.25" eyepiece holder for using the scope with small format cameras or even with eyepieces for visual observing. The back focus is 55mm from the M48x0.75 threaded adapter so Nikon/Canon DSLRs will readily come to focus when used with a wide 48mm camera-specific T ring (not included).
The SharpStar 15028HNT ships with both a Vixen style and Losmandy style dovetail plate, an innovative and attractive carry handle on top, and a hard-sided carrying case.
The total weight of the SharpStar 15028HNT with all accessories is just 5.95kg (13.1 lbs), making it an ideal match for many medium-capacity equatorial mounts.
- 150mm Aperture
- f/2.8 focal ratio / 420mm focal length
- Hyperboloid Primary Mirror made from H-PZ33 Glass (Similar to Pyrex)
- Integrated, triplet, air-spaced corrector
- 44mm Fully Illuminated Imaging Circle
- 6º Field of View
- Carbon Fibre Tube for Strength, Durability, Portability and Thermal Stability
- All CNC Machined Aluminium Parts
- Weighs less than 6kg fully loaded with dovetail / rings / handle!
- 0.77 Arc Seconds Resolution
- 2.5" R&P Precision Focuser with Exceptional Precision and Payload Capacity
- 55mm Back Focus from Corrector
Telescope Field of View Simulator
What's in the box
- 15028HNT Optical Tube
- CNC Tube Rings
- Losmandy & Vixen Style Dovetail
- Eyepiece Adaptor
- Storage Case
|Model ||150F2.8HNT |
|Aperture ||150mm |
|Focal Length / Ratio ||420mm / f/2.8 |
|Primary Mirror Type ||Hyperboloid |
|Mirror Material ||H-PZ33 (similar to Pyrex Glass) |
|Corrector Type ||Air-Spaced Triplet |
|Short Axis Diameter of Secondary Mirror ||70mm |
|Fully Illuminated Imaging Circle ||44mm |
|Actual Field ||6º |
|Main Tube Material ||Carbon Fiber |
|Main Tube Outer Diameter ||195mm |
|Total Length of Telescope ||445mm |
|Net Weight ||4.45kg |
|Gross Weight ||5.95kg (includes tube cap, handle, tube rings and dovetail plate) |
|Resolution ||0.77 Arc Seconds |
|Focuser ||2.5" R&P Precision Focuser |
|Visual Limiting Star Magnitude ||12.7 |
|Focal Plane (Back Focus) ||55mm |
|Camera Connection ||M48 |
|Average Rating (1 Review): |A veritable light bucket, but not without issues
Sunday, 31 January 2021 | Terry
When I first received the 150HNT from FLO (usual quick delivery, etc.), I was really disappointed in the images I got on the first night out, but I quickly realised that this was due to a loose primary mirror - this was either a design or fabrication issue I believe. FLO arranged to get the scope back, fixed the loose mirror issue and returned the scope back to me a fortnight later. I did a quick collimation and had a chance to get it out to grab some images on a less than perfect night (full moon, clouds rolling through, the usual), but managed to get a decent image of M33 with only 30 minutes worth of subs - the sky was too bright to go after fainter stuff so I can't wait for the chance nearer the new moon or with my L-enHance or L-exTreme filter. I have used it with my ASI294MC-Pro - it is a bit undersampled but gives a wider field of view than my ASI183MC-Pro which may be a better match in terms of resolution. A quick scope like this is new to me so it will take a while for me to master collimation - but I managed to sort out my Mak-Newt eventually, so I am not daunted by the prospect, but it will be a steep learning curve all over again. The early images suggest it will be worth the effort. The 4-star review was due to the initial defect of the loose mirror.
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