Price : $750
The TEC Prime Focus Field Flattener corrects field
curvature and off-axis astigmatism. The edge of field
distortion is less than 0.5%. The focal distance
from the flange to the focal plane of the back focus is
79mm for the APO160FL F/7 and 85mm for the APO180FL F/7. The field flatteners can be specifically designed for
the APO160FL F/7 and the APO180FL F/7.