Hi, I have a Nikon DSLR mounted on a tripod. The camera is set to bulb and I expose for the foreground with a long shutter speed and quite a small aperture, somewhere between f5.6 and f11, depending how close the lightning is. This helps not to over-expose the image. I release the shutter using a remote trigger and when lightning happens, I close the shutter almost immediately afterwards. This is also to prevent over-exposure in the event that further lightning strikes happen while the shutter is still open. Thank you for asking. Have you taken lightning photos and were they successful? : )