The total range of the lens type, I want to buy a 1.61 lens, because my degree a little bit high, but I really do not know how to choose? Afraid of shoddy business, I get to sell high-priced 1.56. How differences between 1.61 and 1.56?

The general layman can not see with the naked eye lens and 1.61 lens 1.56 difference. I suggest you go to a regular optical shop testing you will know