Hey there, I bought a brand new UV filter for my nikon 50mm f 1.8 and for my sigma 17-70. I thought it was the best protection for my front glass and wouldn't affect Image quality, but it does! what do you do when you want to shoot portraits with candles for instance ? I keep on having ghosty pictures (duplicated image of the light sources offseted on the top right of the picture. Same problem with high contract image, a bright specular on a reflective object or a window overexpoded for instance. When I remove the filter, photos are clean, sharp and highlights are not offseted. I suppose that people who buy a 6000 $ Leica 50 mm f1.0 will buy a lens protection, but if it affects the image like me, it is not a good solution! is there an alernative way to protect your lens without having this kind of troubles ? thanks!