Quote Originally Posted by randy6 View Post
I have noticed most people spend a lot more money on vintage or collectable muti coated lens is this wise? I was thinking how good of a long term investment can a muticoated lens be? I mean after a number of years most lenes will be aflected with haze or fungus destroying coating's which a newer lens would base the design on the number of air spaces and delicate coating's making a modern lens worthless after time has its way with it. I know a uncoated lens can be etched by fugus but I hardly ever see this. So do you think if you used a hood and filter and did not shoot towards the sun the results would be so poor. I have a leica summicron screwmount the coating has worn off no where to recoat that I know of. Maybe it would be better to collect cheap uncoated lenes what do you think?
That's nonsense.

A lens that is properly cared for will not get fungus. In addition, many lenses that are "diagnosed" with "fungus" have other issues such as lubricant haze, separation, or the blacking on the edges lifting up (Schneideritus). The best way to avoid fungus is to keep the lenses clean - no dirt equals no food, ergo no fungus. Fugus does not "eat" glass or coating.

A lens such as a double Gauss type with 8 air-glass surfaces, six of then internal, is a flare machine. Lubricant haze can and does build up over time, this is exacerbated by high temperatures and misguided efforts to clean/lube shutters (if the lens is mounted in a shutter). Just get coated lenses and take care of them, you'll have no problems.