STEP 2 PREFOCUS FIRST
Once you’re set up with plenty of time in hand before the event is due to happen, it’s time to set the focus, so that there’s one less thing to worry about when you’re shooting as the train steams past. We used an aperture of f/11 to give us great depth of field throughout the scene, so that the whole railway track and train and carriages would be acceptably sharp. We used single-point AF and positioned the focus point over the train track about a third of the way into the frame for optimum sharpness. You can then switch to MF to lock the focus and switch off any IS, which may introduce blur on a tripod. Now boost the ISO until you get a fast shutter speed of 1/200 sec or faster – aslower shutter speed would result in a blurry train.