Forgetting to shield the eyepiece
Did you know that light can enter the camera through the viewfinder and affect the exposure of a picture? Most of the time this doesn’t present a problem, as your face is glued to the back of the camera and shields the eyepiece, but if you switch to Live View, or fire the shutter using a remote release, then there’s a chance that light can leak through the viewfinder. The effect is more obvious in shots take over a long exposure, when strange, ghostly shapes and streaks can be burnt into the image, as can be seen in our photograph of a tree here.
Nikon recommends using an eyepiece cap to block the viewfinder in these circumstances, but you might not have one of these to hand. It’s just as easy to drape a black lens cloth over the top of the camera instead – and you can use it to keep your lens clean, too!