Assertion: newtonian telescope's length | /r/HasProperty | fl
Facets:
Source sentences:
text: I really shouldn’t complain about the 762mm focal length (FL) of the 6″ Meade, some amateur astrophotographers start out with an 8″ SCT with a demanding 2000mm+ FL.
text: It has an aperture of 102mm and a focal length (FL) of 1000mm.