Why Purchase from All-Star Telescope?
Free Expert Support
Whether you are a first timer needing help with setting up or an enthusiast that can't quite make that one thing work, our expert staff are ready to support your needs. With decades of knowledge and first hand experience we've been there and we can help you through it!
Stress Free, Secure Transactions
You can trust purchasing and delivery with All-Star Telescope. All of our transactions are 100% secure and Level 1 PCI DSS compliant thanks to Shopify's ShopPay platform. For additional protection, we insure 100% of the value of every shipment we make. If it get's lost during shipment, we replace it. If it gets damaged during shipment, we replace it. We make sure your product arrives exactly as you would expect it to; we promise.
We also ensure privacy protection. We never keep any of your credit card information on file and any of your personal data is stored according to our policies.
30 Day Return Policy
Buy with confidence knowing that we accept returns up to 30 days after purchase. We want you to have something you will actually use and we are confident that we keep good quality products in our store with No Junk.
Price Match Promise
Shipping around for the best price is tough, we make it easier by offering the best pricing in the market. But if you find a better price on an in-store item somewhere else we will match it!
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Product Description
Designed exclusively for the Askar 131F, this 0.74× reducer reduces the 131F focal ratio to F5.6, unlocking more potential for your imaging possibilities.
This 0.74× Reducer is the ideal companion for the Askar 131F telescope, reducing the focal ratio from f/7.5 to f/5.6. This dramatically shortens exposure times, allowing you to effortlessly capture wide-field nebulae, dense star clusters, as well as faint or fast-moving celestial objects.
It also incorporates field-flattening correction capabilities, effectively eliminating field curvature to ensure sharp, clear stars from the center to the edges of the frame.
Featuring a triplet optical lens design, this reducer supports a 44mm full-frame image circle. It has a standard back focus of 55mm (measured from the M48 thread), with M72×1 threads on both ends. The package includes an extension tube and comes with both M54×0.75 and M48×0.75 adapter rings that connect directly to the reducer for easy installation. The rear adapter ring features a built-in M48×0.75 thread, enabling direct attachment of 2-inch filters.
Constructed using CNC machining, the reducer is equipped with metal thread caps on both ends. These caps protect the optics and offer convenient dust-proof storage, reflecting the product's professional quality.
Specifications
| Parameter | |
| （After attaching）60F Focal length | 733.6mm |
| （After attaching）60F Focal ratio | f/5.6 |
| Lens Number | Triplet design |
| Back Focus | 55mm（from the base of M48 male thread） |
| Weight | 0.56kg |
| Rear-end thread type | M72*1 |
Size Diagram
Installation
Optical Path Diagram
Spot Diagram
