Sharpstar / Askar
Askar FRA500 Quintuplet APO Astrograph
Askar FRA500 Quintuplet APO Astrograph
SKU:ASK-FRA500-APO
Available Soon
Couldn't load pickup availability
Product Description
The Askar FRA500 Quintuplet APO Astrograph is a professional-level astrophotography telescope designed for sharp, flat-field imaging across a wide image circle. It combines a 90mm aperture, 500mm focal length, and fast f/5.6 focal ratio, making it well suited for deep-sky astrophotography.
Its five-element Petzval APO optical system uses a 3+2 lens configuration, including two ED elements in the front group for improved colour correction. The integrated rear field-flattening elements help maintain sharp star shapes across the image field without requiring a separate external field flattener. The telescope supports a generous 55mm corrected image circle, making it suitable for full-frame imaging systems.
The FRA500 also features a robust 3.5-inch dual-speed rack-and-pinion focuser, retractable dew shield, tube rings, carry handle, and Losmandy-style dovetail plate. With its 500mm focal length, the FRA500 offers a useful balance between wide-field framing and additional detail for nebulae, star clusters, and galaxies.
Technical Specifications
| Specification | Details |
|---|---|
| Brand | Askar |
| Model | FRA500 |
| Product Type | Quintuplet APO Astrograph |
| Aperture | 90 mm (3.5") |
| Focal Length | 500 mm |
| Focal Ratio | f/5.6 |
| Optical Design | Petzval Quintuplet APO |
| ED Elements | 2 |
| Corrected Image Circle | 55 mm |
| Back Focus | 158 mm |
| OTA Length – Retracted | 410 mm |
| OTA Length – Extended | 452 mm |
| OTA Weight | Approx. 4.1 kg |
| Focuser | 3.5" Dual-Speed Rack & Pinion |
| Rear Thread | M86 × 1 |
| Conical Adapter | M48 × 0.75 |
| Dew Shield | Retractable |
| Optional Reducer | 0.7× reducer to approximately f/3.9 |
| Mounting Plate | Losmandy-style dovetail |
What's in the Box?
- Askar FRA500 OTA
- Pair of tube rings
- Integrated carry handle
- Askar Losmandy-style dovetail plate
- Conical extender
- User manual
Why Buy the Askar FRA500 from Sky Deep Co.?
Buy the Askar FRA500 Quintuplet APO Astrograph from Sky Deep Co. for genuine astronomy equipment and dedicated support in Pakistan. Sky Deep is an authorized ZWO and Celestron dealer and provides local guidance for astrophotography equipment selection and setup. You can also get help choosing a suitable camera, mount, filter system, reducer, or focusing accessories for your FRA500 setup, along with secure packaging and nationwide delivery.
FAQs
What is the Askar FRA500 best used for?
The Askar FRA500 is primarily designed for deep-sky astrophotography. Its 90mm aperture, 500mm focal length, and f/5.6 focal ratio make it suitable for imaging nebulae, star clusters, galaxies, and other deep-sky targets.
Does the Askar FRA500 need a separate field flattener?
No. The FRA500 uses an integrated Petzval field-flattening design. This helps produce a flat imaging field without requiring a separate external field flattener.
Is the Askar FRA500 suitable for full-frame cameras?
Yes. The FRA500 provides a 55mm corrected image circle, which is larger than the standard 44mm full-frame image circle. This gives it strong compatibility with full-frame astrophotography cameras.
Can the Askar FRA500 be made faster for astrophotography?
Yes. An optional 0.7× reducer can be used with the FRA500 to increase imaging speed to approximately f/3.9 while maintaining full-frame capability.
What focuser does the Askar FRA500 use?
The FRA500 features a 3.5-inch dual-speed rack-and-pinion focuser. It provides coarse and fine focusing control for precise astrophotography and visual observation setups.
