I recently purchased Tokina 11-16mm f2.8 lens for my 1300D Cannon SLR. I notice a half oval shape shadow (small) in the bottom line of the picture is coming when I click any photo with flash. I have tried click without lens hood but it is still coming. The clear photo is only coming if I click photo without flash. If I zoom the lens till 16mm and click with flash then a tiny shadow appears. Without flash, it is working perfectly fine. One of my friend experience the same issue with canon 70-300mm lens. Can anyone help me how to fix this shadow issue? Is this a flash problem or will I need to check my camera to service centre? Or is this a manufacture issue with EOS 1300D? Please help.