Starizona Apex ED 0.65x Reducer / Field Flattener

Description

The Starizona Apex ED is a versatile 0.65x focal reducer and field flattener that works with a wide range of telescope designs — from apochromatic refractors to Ritchey-Chrétien and classical Cassegrain telescopes. It uses extra-low dispersion (ED) glass elements to maintain excellent colour correction while reducing the focal length and flattening the field.

With a 0.65x reduction factor, an f/5.5 apochromatic refractor becomes an incredibly fast f/3.6 astrograph. A slower f/9 RC telescope becomes a speedy f/5.9 system. The reduction provides a 1.5x wider field of view and shortens exposure times by 2.4x — a significant gain for deep-sky imaging.

The Apex ED features a large 44mm clear aperture and covers sensors up to APS-C size with well-corrected, flat fields. It connects via standard M48 threads and has an adjustable backfocus design to optimize performance for your specific telescope.

Key Features

• 0.65x focal reduction with ED glass elements
• Universal design works with refractors, RCs, and Cassegrains
• 1.5x wider field of view, 2.4x faster exposures
• 44mm clear aperture
• Flat, corrected field across APS-C sensors
• M48 connection threads
• Adjustable backfocus for optimal performance

Specifications

Example: An f/7 APO refractor with 500mm FL becomes f/4.55 at 325mm — dramatically faster and wider for astrophotography.