Askar 140APO Triplet APO Refractor Telescope

The Askar 140APO is a large-aperture 140mm f/7 triplet air-spaced apochromatic refractor from Askar (Jiaxing Sharpstar Optical Instrument Co., Ltd.). Designed to serve both serious amateur astrophotographers and professional imagers, the 140APO steps up aperture, light-gathering power, and focuser size compared to smaller APO models in the series, while incorporating a clever retractable lens tube design that keeps overall length manageable. With a limiting magnitude of 12.5 and a 980mm focal length, this telescope excels at deep, detailed imaging of galaxies, nebulae, and star clusters.

Who Is This Product Best For?

• Advanced astrophotographers who need serious light-gathering power in a refractor platform
• Dual-use observers wanting premium image quality both at the eyepiece and through a camera
• Deep-sky imagers targeting galaxies, emission nebulae, and large-format DSOs
• Observatory users seeking a premium refractor for a permanent or semi-permanent setup

Why Choose This Product?

• 140mm f/7 triplet APO optics with one ED glass element for outstanding chromatic correction
• Limiting magnitude of 12.5 — captures fainter objects with more detail than smaller APOs
• Integrated retractable rear lens tube (125mm extension) with rudder-type locking ring — enables binoviewer use when contracted, full imaging with flattener/reducer when extended
• 3.5" dual-speed rack-and-pinion focuser with 1:10 fine adjustment and 10cm travel — larger and more rigid than the 3.3" focuser on smaller models
• 360° high-precision rotator with locking scale for frame rotation without disturbing the mount
• 300mm Losmandy dovetail plate included — ideal for heavy equatorial mounts
• Two finder scope bases on either side of the focuser
• EAF-compatible focuser for motorized autofocus integration
• Portable despite its size — shortest overall length 735mm; gross weight 10.9kg
• Optional 1x flattener (f/7) and 0.8x reducer (f/5.6) — both include built-in 2" filter threads and adapter sets
• Unique identification name ring on every unit

Recommended Uses

• Deep-sky astrophotography with APS-C and full-frame cameras
• High-resolution galaxy and nebula imaging where aperture and resolution matter
• LRGB, narrowband, and SHO filter imaging
• Visual observing with 1.25" or 2" eyepieces and diagonals
• Binoviewer use (rear tube contracted)
• Wide-field imaging with the 0.8x reducer at f/5.6

Compatibility and Accessory Notes

• Rear thread: M84 female; includes 2"/1.25" visual adapters
• Optional 1x flattener: maintains f/7; corrects field curvature and coma; 2" filter thread + M68/M54/M48 adapters included
• Optional 0.8x reducer: reduces to f/5.6; field flattening included; 2" filter thread + M54/M48 adapters included
• Dovetail: 300mm Losmandy standard (included)
• EAF: Compatible with ZWO EAF and most motorized focusers
• Binoviewer: Rear tube contracts for binoviewer compatibility

Important Limitations

• At 10.9kg gross weight, requires a high-payload equatorial mount — look for at least 15–20kg imaging capacity for stable astrophotography
• A flattener or reducer is strongly recommended for full-frame astrophotography
• Not recommended for beginners; best matched to users with EQ mount and imaging experience
• Flattener, reducer, EAF, and additional accessories are all sold separately
• Reducer/flattener adapters use M68/M54/M48 threads — confirm camera adapter compatibility before ordering

Frequently Asked Questions

How does the 140APO compare to the 120APO?
The 140APO offers a 36% larger aperture area, deeper limiting magnitude (12.5 vs 12.2), a larger 3.5" focuser, and an integrated retractable tube design. It requires a heavier mount but delivers more resolution and contrast on faint objects.

What mount do I need?
The 140APO ships with a 300mm Losmandy dovetail. Look for a mount with at least 15–20kg imaging payload — for example, a Skywatcher EQ6-R, iOptron CEM70, or equivalent.

Is the retractable tube design stable?
Yes. Askar engineered the retractable rear tube for rigidity — the optical axis is not affected when the tube is extended, and the rudder-type locking ring secures it firmly.

Can I use it for visual observing?
Absolutely. With the rear tube contracted, connect 1.25" or 2" diagonals and eyepieces. It is also binoviewer compatible.

What cameras is it compatible with?
APS-C and full-frame sensors. For full-frame, pair with the optional 1x flattener for sharp stars edge-to-edge.

Our Recommendation

The Askar 140APO is a serious step up for astrophotographers who have outgrown smaller APOs and need more aperture and resolution. Its retractable tube, Losmandy dovetail, large 3.5" focuser, and deep limiting magnitude make it ideal for high-end imaging setups. Choose it if you have a suitable heavy-payload mount and want one of the best mid-large refractors available at its price point. Not recommended for beginners or those with mounts rated below 15kg imaging payload.

Optical Diagram Reports

The following optical reports and technical diagrams are provided by Askar for the 140APO: