The iOptron field flattener reduces the normal field curvature inherent in all refractors to provide you with images that are sharply focused out to the very corners of your 35mm or large format CCD imager frame. Stars look sharp and point-like all the way across the field.
This 2” iOptron field flattener is designed for iOptron’s Versa 108 ED refractor, but also is compatible with f/5 to f/7 refractors.