Focal reducer Askar 91F 0.75x

Name: Focal reducer Askar 91F 0.75x
Brand: Askar
SKU: ASKRED91F
Price: 198.31 EUR
Availability: PreOrder

Reference ASKRED91F

Stock at Supplier

198.31

VAT excluded Shipping 5/7d

The Askar 0.75x reducer for the 91F is specially optimized to unlock greater capabilities in astrophotography.

Buy it now and receive it between on Monday, 29 December and Monday, 5 January with Home delivery - International

Delivery Options

Carrier		Description	Estimated Delivery
	Home delivery - International	Home delivery - International	Monday, 29 December - Monday, 5 January

Home delivery - International

Estimated delivery:
Monday, 29 December - Monday, 5 January

✖

Description
Product Details

The 0.75x reducer can lower the focal ratio of the Askar 91F to F5, providing not only a faster focal ratio, but also a built-in flattened field correction. The shorter focal ratio offers a wider field of view and faster exposure time, making it ideal for capturing large areas of nebulae, star clusters, and faint, fast-moving celestial objects.

The 91F 0.75x reducer adopts a triplet design and supports a 44mm full-format image circle. Rear focus from the M48 thread is 55mm standard. Both end threads are M59*1. The 91F photographic extension tube includes M54×0.75 and M48×0.75 adapters for direct and convenient connection to the reducer 0.75x.. The reducer features a built-in 2-inch M48*0.75 filter thread, allowing direct installation and use of filters. The whole reducer is CNC machined and comes with metal threaded caps on the front and back to protect it from dust when not in use.

Parameters
After mounting）91F Focal length 455 mm
After mounting）91F Focal ratio f/5
Number of lens Triplet design
Backfocus 55 mm（from base of male thread M48）
Weight 0.3 kg
Rear thread type M59*1

Optical Path Diagram

Spot Diagram

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