Back Focus Button
How to make this type of photo? If your object you want to photograph is moving fast and is moving in your direction. First and most important factor is, you need a good looking dog like my Ema. Second thing you need is to have nice location, with good light. so, to get blur behind my dog i use nikon lens 70-200 2.8 i set my camera on 2.8 so i get blur. Now, to maximize my blur i set my lens to 200mm and i position myself in closest distance to get the frame i want. That's how you get the bokeh blur effect.
But there's more to it. My object is moving fast and is moving to my direction. what to do ? We all know that, focusing is hard in situations like this. First, your shutter speed need to be fast, very fast. i would suggest to be on safe side and set to 1/800 minimum. if the light condition aloud you so set it faster. f/2.8 aperture can be pain to work with, if your object is moving, little move of your camera cant take you out of focus. You can set to f/5 and plus but then you ill loose your blur. We don't want that, we want nice blur. so lets keep 2.8. Of course if you have lenses with 1.8 or 1.4 you can set them to your minimum.
But the main trick in this kind of photographs is your auto focus system. Af-c continuous focusing is the way to go. and back focus button is the way to go. Back focus button called AF-ON which is in the back of your camera. Why is good AF-On button ? because that is specific job for this button , just to focus. Normally half press shutter button is focuses and full press is making a picture. If you use you AF button and you hold pressed, is continuously focuses on your object. and while you hold it pressed, you can make pictures by pressing your shutter button. If you use just shutter button to focus and to shoot ,after every shot your camera need to refocus. Which mean you loosing the time and moments you want to capture. I would recommend you to start using that AF button. More info join my workshops