When overexposure works in your favour: Sometimes, an overexposed shot can give you a dramatic effect. In this picture, we used an aperture of f/19, an ISO speed of 200 and a shutter speed of 68.6 seconds. The bolt was so intense it ended up looking a tornado. We would like to say we planned it, but the bolt was so bright it caught us by surprise — and almost blinded us. We had to use a smaller aperture for the next shot.