Sharpstar Z4 100mm f/5.5 Sextuplet APO Astrograph OTA
Product Overview
The Sharpstar Z4 100mm f/5.5 Sextuplet APO Astrograph is designed for astrophotographers who demand precision, portability, and superb optical performance. With a fully corrected field, this fast astrograph eliminates the need for a separate field flattener, delivering sharp, pinpoint stars right to the edge of your frame.
Lightweight and easy to carry and assemble, the Sharpstar Z4 is equally at home on a portable mount or a permanent observatory setup.

Key Features
- 100mm Sextuplet APO design – six optical elements for exceptional colour correction.
- f/5.5 fast focal ratio – gather more light in less time for deep-sky astrophotography.
- 300mm Vixen-style dovetail plate – secure and reliable mounting for most equatorial mounts.
- Precision focuser with smooth focusing and angle adjustment for accurate framing and fine focus control.
- Full-frame imaging circle – perfect for modern CMOS and DSLR cameras.
- Compact and portable – ideal for travel or field use.
Benefits for Astrophotographers
- Capture stunning wide-field nebulae and galaxies with excellent star sharpness.
- Save time with a built-in flattener — no extra accessories required.
- Lightweight OTA ensures easy setup, focusing, and framing even on mid-range mounts.
- Compatible with standard accessories thanks to its Vixen-style dovetail plate.

What’s Included
- Sharpstar Z4 100mm f/5.5 Sextuplet APO Astrograph OTA
- CNC-machined tube rings and handle
- 300mm Vixen-style dovetail plate
- Carry case for transport and storage
Specifications
- Aperture: 100mm
- Focal Length: 550mm
- Focal Ratio: f/5.5
- Optical Design: Sextuplet APO (6 elements)
- Back Focus: 55mm
- Weight: Approx. 5.5kg
Why Choose the Sharpstar Z4?
Whether you’re imaging from a dark-sky site or your backyard, the Sharpstar Z4 delivers professional-grade results with ease. Its optical quality, portability, and versatility make it one of the best choices for astrophotographers seeking wide-field precision in a compact design.

Frequently Asked Questions
Does the Sharpstar Z4 require a field flattener?
No. The Z4 is a sextuplet design with a built-in flattener, providing a flat imaging field across full-frame sensors.
What type of dovetail plate does it include?
The Sharpstar Z4 comes with a 300mm Vixen-style dovetail plate for secure mounting.
Is the Sharpstar Z4 easy to transport?
Yes. At only 5.5kg and supplied with a carry case, the Z4 is lightweight and easy to carry and assemble.