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I just took these earlier with my kit lens. I have a problem shooting sometimes, when i'm in manual mode i don't know the exact iso, f#, or shutter speed but i have focus on AF.S and when i press the shutter release it'll try to focus but won't fire and the hexagonal icon flashing in the viewfinder. But when i aim it at a brighter scene, it fires. It'll also fires when after i changed the focus to AF.C. So my question is what is the flashing hexagonal icon mean? and also, why it would take photo in a brighter scene and not the darker one (when focus is on AF.S)?