William Optics Fluorostar 120
- 120mm Aperture
- FPL-53 Triplet Apochromatic Optics
- 3.3" Rack & Pinion Focuser
- Built-in Camera Angle Rotator
- Integrated Bahtinov Mask
The William Optics Fluorostar 120 refractor combines a 120mm apochromatic triplet objective made with FPL-53 glass and a robust 3.3" rack and pinion focuser for high-contrast, color-free astrophotography. Its imaging train begins with a native M92 thread and includes adapters for a 2" RotoLock and a 1.25" visual back, ensuring broad compatibility with your cameras and accessories.
At the heart of the Fluorostar 120 lies an air-spaced triplet objective featuring premium FPL-53 glass. This apochromatic design provides outstanding correction of chromatic aberration, eliminating the false color halos around bright stars that can compromise contrast and detail in lesser refractors. The result is a pristine, high-contrast image with pinpoint stars on a dark background, essential for capturing the subtle colors of nebulae and galaxies.
Built to handle heavy imaging loads, the heavy-duty 3.3" rack and pinion focuser provides a rigid, zero-flexure platform for large cameras, filter wheels, and off-axis guiders. A built-in rotator allows you to frame your target perfectly without loosening the camera. The robust build necessary to support a full imaging rig means this is not a lightweight instrument; you will need a substantial mount to carry it effectively.
The Fluorostar 120 is engineered with practical features that streamline your imaging sessions. An integrated, patented Bahtinov Mask, built into the lens cap, is significantly lighter than traditional metal masks and makes achieving critical focus simple. The CNC-machined saddle handle bar not only provides a secure grip but also accepts Vixen-style mounting for guidescopes like the William Optics Uniguide. The entire optical tube assembly is secured by a sturdy Losmandy-style dovetail plate for a solid connection to your equatorial mount.
The FPL-53 glass in the Fluorostar 120's triplet lens system provides excellent correction of chromatic aberration. This means stars appear as sharp, color-pure points of light without distracting purple or blue halos, resulting in higher contrast and more natural-looking astrophotos.
The patented Bahtinov Mask is built directly into the lens cap of the Fluorostar 120. To use it, you simply uncap the telescope, aim at a bright star, and adjust focus until the central diffraction spike is perfectly centered between the other two. This provides a fast, precise, and repeatable method for achieving critical focus every time you set up.
The heavy-duty 3.3" rack and pinion focuser is designed to handle significant weight without slipping or flexing. It can easily support a full astrophotography setup, including a cooled astronomy camera, a large filter wheel, and an off-axis guider, ensuring your entire imaging train remains stable throughout the night.
The Fluorostar 120's apochromatic optics excel at imaging emission nebulae like the Veil Nebula. The high-contrast views and excellent color correction allow the fine, filamentary details of the hydrogen-alpha structures to be captured with exceptional clarity against a dark sky background, especially when paired with narrowband filters.
The built-in camera angle rotator on the Fluorostar 120 lets you adjust the orientation of your camera without having to loosen any other components in the imaging train. This is crucial for large targets like M31, as it allows you to precisely align the galaxy's long axis with your camera sensor's diagonal for the most compelling composition.
The William Optics Fluorostar 120 comes with essential mounting hardware for immediate setup. This includes a CNC-machined handle that doubles as a Vixen-style saddle for accessories, mounting rings, and a Losmandy-style dovetail plate for secure attachment to a compatible equatorial mount.
| Available Options | Red, Gold, Space Gray |
M92 Rotator Adapter
× 1
M92 to 2" RotoLock Adapter
× 1
2" to 1.25" Visual Back Adapter
× 1