Hi all, My better half is using a Canon 5 with my old (+- 5 years) 24-105 lens. The lens is in perfect condition and has only ever been used by myself. Recently some strange anomalies started appearing on her pictures. On both the left and right of the pictures, although mostly left hand side, strange concentric circular lines are appearing. It is not on all pictures on a roll and it does appear on different rolls from slide to BW. I have attached a picture of the problem (see light circles on left of picture), but this one is not as pronounced. I will post more later that are extreme. Some pictures are with a filter (red) and some without. The lens was bought about 4-5 years ago, new, for a digital camera. The Canon 5 that she has needs a CLA but there are pictures from another lens that are perfect. This problem appears to occur intermittently with the one lens, the 24-105. Is it the glass? Is it the mount? Light leak? Please can someone help me identify this?