I have a Nikon D80 kit lens with a circular screw-on polariser filter. In order to remove the filter I might have to grip the lens quite hard, and the end of the lens might be moved about in the radial direction somewhat relative to the rest of the lens. I was wondering if this could cause damage to the lens.
A few years ago I took the camera and lens to a Greek island and noticed that a lot of my shots appeared soft, and with more chromatic aberration than normal. This seemed to persist for a while after I got back, but seems to be fine now, and I had forgotten about it. But could this have been caused somehow by my attempts to remove the filter at some earlier point? Maybe it caused an element in the lens to become slightly askew?