Sytrony Japan Launches '60F 0.75x Reducer' and '91F 0.75x Reducer' to Enhance Askar F-Series Performance
Sytrony Japan will release specialized 0.75x reducers for the Askar 60F and 91F telescopes on May 22, 2026. These reducers shorten focal length by 0.75x, providing brighter optics and a wider field of view for easier imaging of nebulae and star clusters. They support full-frame sensors and include built-in filter mounts. Estimated market price is around 30,000 JPY each.
📋 Article Processing Timeline
- 📰 Published: May 22, 2026 at 20:00
- 🔍 Collected: May 22, 2026 at 11:31
- 🤖 AI Analyzed: May 22, 2026 at 12:13 (41 min after Collected)
Sytrony Japan announced the release of the '60F 0.75x Reducer' (for Askar 60F) and the '91F 0.75x Reducer' (for Askar 91F), products from the Jiaxing Ruixing Optical Instrument brand 'Askar,' on May 22, 2026. By shortening the focal length of each telescope by 0.75x, these reducers allow for brighter f-ratios and a wider field of view, making the imaging of nebulae, star clusters, and faint deep-sky objects more efficient.
■ Key Features
- Specifically Designed 0.75x Reducers
Optimized for each model, the 60F setup achieves 311mm f/5.1, while the 91F setup achieves 455mm f/5. Shortening the focal length widens the field of view, helping to reduce exposure times.
- Full-Frame Compatibility
The optical system uses a 3-group, 3-element design and supports a 44mm full-frame image circle. Back focus is 55mm from the M48x0.75 connection point.
- Streamlined System Integration
The reducer connects inside the existing extension tube provided with each telescope. The adapter section includes a built-in M48x0.75 filter thread.
■ Key Features
- Specifically Designed 0.75x Reducers
Optimized for each model, the 60F setup achieves 311mm f/5.1, while the 91F setup achieves 455mm f/5. Shortening the focal length widens the field of view, helping to reduce exposure times.
- Full-Frame Compatibility
The optical system uses a 3-group, 3-element design and supports a 44mm full-frame image circle. Back focus is 55mm from the M48x0.75 connection point.
- Streamlined System Integration
The reducer connects inside the existing extension tube provided with each telescope. The adapter section includes a built-in M48x0.75 filter thread.
FAQ
Askar 60F用および91F用レデューサーの主なメリットは何ですか？
焦点距離を0.75倍に短縮することで、より明るいF値と広い視野を得られ、露出時間を短縮できるため、星雲・星団などの淡い天体の撮影をより軽快に行えます。
対応するイメージサークルはどれくらいですか？
φ44mmのフルサイズイメージサークルに対応しています。
レデューサーにはフィルターを直接取り付けられますか？
はい、アダプター部にM48×0.75の48mmフィルター取り付けネジを内蔵しており、追加アダプターなしでフィルターを装着可能です。
発売日と予想市場価格を教えてください。
発売日は2026年5月22日（金）で、予想市場価格はそれぞれ税込30,000円前後です。
どこで購入できますか？
天体望遠鏡専門店および株式会社サイトロンジャパンの直営店限定での取り扱いとなります。