Introducing the WILLIAM OPTICS Internal Focus Design (WIFD) Apochromatic Series. This innovative and revolutionary design combines a precision (Patented) internal focusing mechanism with the highest quality optics available, providing the ultimate Apochromatic refractor for astrophotography. Designed from the ground up with the ability to handle the newest generation of large, heavy, high-resolution cooled cameras, the rock-solid optical tube assembly is uncompromised in quality. The movement of the focuser is integrated inside the main tube assembly, so there are no movements of a focuser drawtube visible from the outside.  The user can enjoy the benefits of a traditional two speed fine focuser, while not worrying about limitations typically found in traditional rear mounted focusers. 

INTERNAL FOCUSER DESIGN

NEW internal focuser.  Our new design includes the Patented WO center focuser with precise internal sliding of fixed optics to prevent image shift.  The integrated position viewing window on the focuser provides instant verification of the graduated numerical display.  The smooth rack and pinion design is incorporated into the focuser to provide super fine adjustability for critical focus.  The internal movement of the optical elements is protected from the elements and can’t come out of alignment.  The redistribution of weight allows for better balance during imaging sessions.