Af-s Nikkor 18-55 1:3.5-5.6G VR lens issue

I have been using this Nikkor 18-55mm lens that came with my D5000 kit. I have taken thousands of picture and never had a problem. Two days ago I was taking some pictures outside. All was going well and then all of a sudden, it fogged up on me. It was very hot and humid. I first thought it was the humidty on the out side of the lens, however it was not. I changed to my 35mm lens and it was not a problem. I did clean the lens that morning with a cleaning fluid. Is it possible some leaked into the inside causing the problen?

I have used it this that happened with no problems.

thanks nepsa

It could be your problem if you put the fluid directly on the lens and then used a cloth or whatever to do the cleaning. Fluid can then be forced into the lens body itself during the wiping process, especially any lens not manufactured as weather resistant. Rule of thumb is cleaning solution on cloth then wipe clean.

Another possibility is the fact that plastic contracts when subjected to heat and that could have happened to your lens, allowing any excess cleaning fluid to enter the lens.

Yes even a small amount of moisture inside the lens will transpire to vapor because of the greenhouse effect inside the lens housing (just like inside a car). So that could be why. I never let any cleaning fluids, even lens cleaning fluids I use for microscope objectives at my place of work, touch my lenses because you never know how they will react with the lens coatings. My method is just to lightly breath on the lens then immediately but gently wipe in a circular motion with lens paper or soft lens cloth (or even a clean cotton shirt).

Thanks for your comments. I did put the cleaner directly on the lens. I have learned a lesson and will no longer use that process. thanks again.