This is taken from another thread I posted in and didnít get any responses. The thread was complaining
about the lack of training and understanding being exhibited by many of todayís opticians.
letís see how many answers I get to this question. I have used this in the past about 25% knew the answer.
which of the following items can you use to find the optical center on a lens the two lenses in the list are not the lens you have to find the center

1 pencil
2 marking pen
3 piece of paper
4 +1.00 sph
5 -1.00. Sph
6 caliper
7 microscope
8 mm scale

After you select the items needed how would you proceed