The student disassembles the lens from the dslr.
text: No, this is the cover. The camera lens.
text: So, you press and hold the button, the black button on your left hand, on the EOS.
text: The other side. There is EOS mark.
text: Here?
text: Yes.
text: Press and hold the black one.
text: This one?
text: Yes.
text: And turn the red mark.
text: Alright.