Bright field (BF)and dark field(DF)are the two basic ways to form amplitude-contrast image (A) TEM (B) TEM Incident beam Specimen Objective To TEM imaging diaphragm To TEM imaging system(BF) system (DF) 6 (p.99 in the textbook)Bright field (BF) and dark field (DF) are the two basic ways to form amplitude-contrast image 6 (p.99 in the textbook)