Askar 0.76x Reducer for 80PHQ

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0.76x reduction factor specifically for the Askar 80PHQ Reduces focal ratio from f/7.5 to a faster f/5.7 Creates a new focal length of 456mm Generates a 44mm image circle, fully il luminating full-frame sensors Maintains a standard 55mm backfocus for easy camera connection Features an integrated M48x0.75 filter thread Description FAQ Specifications In the Box Downloads Warranty Askar 0.76x Reducer for 80PHQ This Askar 0.76x Reducer is engineered specifically for the 80PHQ astrograph, transforming its native f/7.5 optics into a faster f/5.7 imaging system with a 456mm focal length. The 3-element air-spaced triplet design delivers a corrected 44mm image circle, fully illuminating full-frame sensors while maintaining a standard 55mm backfocus for straightforward integration with your camera and filter wheel. A Triplet Design for f/5.7 Speed and a 456mm Focal Length By decreasing the focal ratio of the 80PHQ from f/7.5 to f/5.7, this 0.76x reducer shortens required exposure times by approximately 42%, allowing you to capture more signal in less time. The resulting 456mm focal length provides a wider field of view, ideal for framing large nebulae and star clusters. The internal 3-element triplet lens configuration ensures that the wider field remains sharp and well-corrected across the frame. Full-Frame Imaging: 44mm Image Circle and Standard 55mm Backfocus The reducer is designed to produce a 44mm image circle, providing full, unvignetted illumination for cameras with full-frame (36x24mm) sensors. It connects directly to the 80PHQ's focuser and features a standard 55mm backfocus, simplifying the process of attaching a DSLR, mirrorless, or dedicated astronomy camera with the correct spacing. An integrated M48x0.75 (2-inch) filter thread allows you to easily add light pollution or narrowband filters into your imaging train without needing a separate filter drawer. What does the Askar 0.76x Reducer do for my 80PHQ telescope? The Askar 0.76x Reducer converts your Askar 80PHQ from its native f/7.5 focal ratio to a faster f/5.7. This shortens your exposure times and provides a wider field of view with a new focal length of 456mm, making it better suited for capturing large deep-sky objects. Is the 44mm image circle of this reducer large enough for my full-frame camera? Yes. The 44mm image circle is specifically designed to be larger than the diagonal of a standard full-frame sensor (which is approximately 43.3mm). This ensures your full-frame camera sensor is fully illuminated without vignetting caused by the reducer. How do I connect my camera to the Askar 0.76x Reducer for the 80PHQ? The reducer provides a standard 55mm backfocus from its rearmost thread. This is the standard spacing for most cooled astronomy cameras when used with a filter wheel, or for a DSLR/mirrorless camera with its corresponding M48 T-ring. You simply add the necessary M48 spacers to achieve the 55mm distance to your camera's sensor. How does the f/5.7 speed help when imaging the Andromeda Galaxy (M31) with the 80PHQ? The Andromeda Galaxy (M31) is a very large target that benefits from the wider 456mm focal length. More importantly, the faster f/5.7 optics gather light more quickly than the native f/7.5, allowing you to capture the faint outer arms and dust lanes of the galaxy with shorter individual exposures, improving your overall signal-to-noise ratio in a single imaging session. Can I use filters with the Askar 0.76x reducer? Yes. The reducer has a built-in M48x0.75 (2-inch) filter thread on the camera side, allowing you to easily screw in standard 2-inch mounted filters for light pollution reduction or narrowband imaging. Will this 0.76x reducer work on telescopes other than the Askar 80PHQ? No, this reducer is specifically designed and optically matched to work with the Askar 80PHQ astrograph. Using it on other telescopes will likely result in poor optical correction, field curvature, and an inability to reach focus. Reducer Type 0.76x Focal Reducer Compatible Telescope Askar 80PHQ Resulting Focal Ratio f/5.7 Resulting Focal Length 456mm Optical Design 3-element, air-spaced triplet Image Circle 44mm Back Focus 55mm Filter Thread M48x0.75 (2-inch) Max Outer Diameter 68mm Askar 0.76x Reducer for 80PHQ × 1 Download Software & Drivers Askar 1-Year Warranty Show more