Just picked up this lens at a garage sale of all places...real cheap. Put it on my Nikon 300s and it worked fine. Took it home and naturally cleaned the front and rear elements. While cleaning the front element, I noticed that the next two internal elements appeared to have corruption of the lens coating in multiple places. I took a few test shots, and none appear to be compromised by the problem. I'm sure if I drilled down deeply, I could find some image diffusion as a result, but I'm just not that crazy about my image quality. I'm an amateur...not pro. This is my first non-Nikon lens, and It just bothers me to see some element issues in this lens. Should I try to have these recoated or something? And since I only paid $50 for the lens, is the repair going to be 4 or 5 times the cost of the lens? Thanks to all.

Cameras - Tamron - 200-400mm F/5.6 LD Lens