Assertion: true eyepiece | /r/HasProperty | manufactured by carl zeiss
Facets:
Source sentences:
text: At the beginning of page 31 in Chris Lord's 'Evolution of the Astronomical Eyepiece', he states, "The true Plössl eyepiece, as manufactured by Carl Zeiss, and after W.W.II by ets Clavé and now Kinoptique, has the crown elements almost in contact (the separation can be as little as 2 thousandths of an inch), and the eye doublet has a shorter focal length than the field doublet.