The Starizona Apex ED reducer transforms an f/5.5 APO refractor into a whopping f/3.6 astrograph! Slower telescopes like those at f/9 can become as low as an f/5.9 system. On top of this, you'll enjoy a 1.5x wider FOV and exposure shortened by more than double the time!
The Apex ED reducer features extra-low dispersion glass to eliminate chromatic aberration and to provide sharp star images over a 30mm image circle, capable of working with most popular CCD, CMOS, and DSLR cameras up to APS-C format.
Fitting into a standard 2-inch focuser, the Apex ED reducer has M42 T-threads on the camera side and can accommodate 2-inch (M48) filters on the telescope side for easy customization. You can also attach this to a 2-inch visual back with Meade ACF telescopes especially.
"L" and "S" Versions
The Apex ED is available in two versions. The "L" version is designed for telescopes with focal lengths 500mm and longer. This includes most larger (100mm+) refractors and all RC and ACF telescopes. The "S" version is for telescopes with focal lengths from 300-500mm, including most 60-80mm APO refractors.
The nominal backfocus distance from the Apex ED reducer's T-threads to the image sensor depends slightly on the focal length of the telescope. It is at least 55mm in all configurations. The table below shows the optimum backfocus for various focal lengths. Please contact us for help in choosing the right adapters or spacers necessary for your setup.
Designed for APO refractors, but also works with RC and ACF telescopes
Corrects for optical curvature and produces pinpoint stars essential for astrophotography
This is the "Short" version designed for telescopes with a focal length under 500mm.