ToupTek GS-250AC 50mm Aperture PAPO f/5 High Precision Astronomical Guide Scope with FSB-125C Rackless Focuser

ToupTek GS-250AC 50mm Aperture PAPO f/5 High Precision Astronomical Guide Scope with FSB-125C Rackless Focuser

Difference:
- Rackless Focuser (AC versions): FSB-125C rackless focuser with precision bearing guides and a classic Crayford-style mechanism for smooth focusing and stable optical alignment—ideal for light-load manual imaging.
- Rack-and-Pinion Focuser (AR versions): FSB-125R gear-driven focuser with precision bearing guides for higher focusing accuracy; compatible with ToupTek Astro AAF electronic focuser, suitable for autofocus and heavier payloads.

PAPO Apochromatic Optical Design, True Star-Color Reproduction:
- The GS Series guide scopes feature a proprietary three-element PAPO (planar apochromat with integrated field flattener) configuration with one ED element, effectively correcting chromatic aberration, astigmatism, and field curvature. Designed around a flat, well-corrected 1-inch image circle, they deliver crisp, pinpoint star images for accurate guiding, while also supporting visual use and entry-level night-sky/DSO imaging.

High-Transmission Coatings + Anti-Reflection Threads, Boost Guiding Sensitivity:
- All optical surfaces use broadband multi-layer AR coatings to minimize reflections and maximize transmission. The internal barrel is precision-machined with anti-reflection threads and additional stray-light suppression, greatly improving image contrast.

CNC Precision Machining, Fine Matte Finish:
- The tube, rings, and dovetail plate are CNC-machined from aluminum alloy for a balance of low weight and structural strength. Anodized surfaces provide wear and corrosion resistance suited to field astronomy. The fine matte texture is comfortable, durable, and non-slip.

Modular Structure for Maximum Flexibility:
- A proprietary universal M48 extension tube with anti-reflection treatment forms the main barrel, allowing flexible combinations to match optical path requirements - from visual observing to astrophotography.

Wide Compatibility · Rich Configurations, Seamless System Integration:
- Built for flexibility: support for 1-inch sensors, direct threaded connections, and multiple mounting points let the GS Series integrate smoothly with a wide range of cameras and setups.

Package Included:
- 1 x Guide Scope
- 1 x Dust Cover

Note:
- The GS-350 guide scope displayed in the picture is out of stock, for demonstration only.