Good day, I have a used Schneider-Kreuznach Componon-S 5.6-135mm Enlarging Lens for sale. It is made of metal. The lens has been exposed to humidity at one time and consequently the coating is mottled. There a specks of dust and what looks like tiny air bubbles in the elements. This lens was given to me but I never used it. I would assume that the flaws mentioned above would reduce the contrast which can be a benefit under some circumstances. The lens comes with front and rear caps. I am asking $45.00 Thank you