I have a customer that has a hand held lens that he calls a reduction lens, it is 3" in diameter with a handle like a magnifier. I measure the power and find -4.00D, biconcave lenses -2.00D each side. He is an artist that uses it to stand in front of a painting at about 3 feet and it allows him to see the entire painting 6'-8' wide. He needs to get a replacement and I have not had any luck finding one. Does anyone know where I could find one?
Thanks