Askar FMA180 Pro 40mm f/4.5 APO Astrograph

Product Overview

The Askar FMA180 Pro is a compact 40mm f/4.5 sextuplet air-spaced APO astrograph designed for deep-sky astrophotography and visual observation. Building on the original FMA180, the Pro model introduces a 360° camera rotator, integrated finder base with bracket, and an internal focusing mechanism — all in a lightweight 0.8 kg package that delivers outstanding chromatic aberration correction across a 44mm full-frame image circle.

The sextuplet optical design uses a three-lens-front, three-lens-rear configuration with two ED (extra-low dispersion) glass elements, providing excellent colour correction and contrast across the full image field. The result is a sharp, flat, and colour-neutral image from edge to edge — well-suited for both one-shot colour and monochrome camera setups.

Key Features

• Sextuplet APO Design — Six air-spaced lenses with 2× ED glass for exceptional chromatic aberration correction
• Internal Focusing Mechanism — Promotes stability and eliminates image shift during focus adjustments
• 360° Camera Rotator — Allows framing adjustments without repositioning the mount
• Integrated Finder Base & Bracket — Supports guide cameras or finder scopes directly on the OTA
• 150mm Vixen Dovetail Plate Included — Ready to mount on any Vixen-compatible saddle
• Full-Frame Coverage — 44mm image circle supports APS-C and full-frame sensors
• Built-in Field Reducer — Optimized optical path for fast f/4.5 imaging
• Built-in 2" Filter Thread — M48×0.75 rear connection with integrated 2" filter thread for narrowband or broadband filters
• Dual Use — Can be used as a standalone astrograph or mounted to another telescope's finder base as a guide scope (with Vixen plate detached)
• Compact and Lightweight — 167.5mm total length and 0.8 kg make it ideal for travel, dual-rig setups, and lightweight mounts

Optical Design

The FMA180 Pro uses a sextuplet air-spaced APO configuration — three lenses in front and three in the rear — two of which are ED glass elements. This design provides the chromatic aberration correction of a premium apochromat in a physically short tube, enabling a fast f/4.5 focal ratio at just 180mm focal length. The 55mm standard back focus and M48×0.75 rear thread ensure compatibility with a wide range of imaging cameras, filter drawers, and off-axis guiders.

What's New Compared to the FMA180

• Added 360° rotator for framing flexibility
• Added integrated finder base and bracket for guide scope or finder scope mounting
• Internal focuser design replaces external focuser for improved rigidity
• 150mm Vixen dovetail plate included in the package

Imaging Performance

The FMA180 Pro has been used to image a wide range of deep-sky objects including the Rosette Nebula, Orion Nebula, Spaghetti Nebula, Horsehead Nebula, IC 443, NGC 2174, and more — paired with cameras such as the ZWO ASI2600MM Pro, ASI294MC, and ASI294MM Pro. Its fast focal ratio and full-frame coverage make it well-suited for wide-field nebula imaging, Milky Way photography, and multi-panel mosaics.

Specifications

What's in the Box

• Askar FMA180 Pro OTA (with integrated rotator and finder base)
• 150mm Vixen dovetail plate
• M48×0.75 rear adapter
• Instruction manual

Compatibility Notes

• Camera connection: M48×0.75 with built-in 2" filter thread
• Standard 55mm back focus is compatible with most imaging cameras and filter accessories
• Works as a guide scope or finder when mounted via finder base bracket (Vixen dovetail removed)
• Compatible with ZWO ASIAIR, N.I.N.A., Ekos/KStars, and other capture platforms via standard M48 connection
• AF Kit available separately (Askar FMA180 Pro AF Kit — SKU: FMA180PRO-AF-KIT)