Hey guys, quick question:
Is it normal that the lens very often makes the same sound as the aperture changing even though it's on manual and staying at the same f-stop? Seems to happen when I move the camera to a different lighting or when I half-press the shutter to focus, all of a sudden it makes that very short but noticeable aperture change sound.
My 50D is not on Live View and my finger is not holding the DOF preview button..therefore I can't see a reason why the aperture would sound like it keeps shifting. Keep in mind, the camera's f-number never changes..again, it's on manual. Is it related to IS? My previous IS lens didn't do that I don't think.
Any ideas? I never had this happen before on any other lenses, even IS.