The book comes from a long and complex research carried out in Italy, Europe and America. We have collected millions of data that we then worked with programs created on purpose. The result is over 1900 estimates of camera lenses. The brands of the camera lenses are 124. Estimates are provided with a range of values between a minimum and a maximum. These two extremes are the weighted averages of the offers found on the market. For each goal, in addition to the make and model, they are provided: the focal length, the maximum brightness and the type of attack on the camera if that affects the estimate. A book that, along with "Cameras estimates 1900-2000," is a valid tool collectors, antique dealers, retailers and everyone who wants to sell or a lens used or old.