Archive for septembre 12th, 2010

Manual focus series III : Focus by anticipation

Dimanche, septembre 12th, 2010

Skill : advanced
In focus rate : 80%
Shot style : Moving subjects, preset compositions

Yesterday I wrote about how to preset your focus and then move into position to frame and trigger. Today’s focus technique is a variation of zone focus, yet in this case you will first position yourself, set the focus then wait for your subject to enter your frame. This method is most useful when facing fast moving subjects (bikes, cars, joggers… ) or whenever you have identified a specific background and wait for a subject to enter it. But let’s go directly to the pictures to illustrate that method.In the first picture taken on a bridge of the Canal St-Martin, I spotted this lady on her bike as she was stopped at a traffic light on the other side of the Canal. I therefore quickly identified the best composition possible from my position as moving around was not an option due to the imminence of her arrival. I then set the focus on one of the white stains on the ground (chewing gum residue I suppose) where I expected her to ride by. As she progressed towards me, I had to slightly modify my focus point as her path was different from the one I had expected initially. Yet as she entered my viewfinder, I was ready and only had to click. As you can tell from her dress, she was riding quite fast so a manual focus as she moved in the viewfinder would have resulted impossible, especially since my lens was wide open at F1.4. (click on picture to enlarge)

anticipation-focus-i-lr.jpg

Leica M8 with 50mm Summilux asph at F1.4, 1/1000, ISO160

The second picture illustrates a variation of this technique, more adapted to situations where the subject will enter your frame close to you. Indeed in this case, it is less effective to pre-focus on a ground pattern since you will always re-frame significantly afterwards, which will in turn result in an overshoot of the real focus point (as stated by the laws of geometry). In this situation, it is best to simply estimate the distance at which your subject will be located in your composition and adjust the focus distance on your lens accordingly. In the picture below, I spotted this musician at a pedestrian crossing in front of the Saint-Augustin Church. I identified a potential composition with the church in the background and estimated that the boy would be in focus about 2 meters in front of me. I therefore set the focus distance on my lens and kept the aperture at F1.4 for a strong out of focus effect in the background. As this young musician finally entered my viewfinder, all I had to do was to remain steady and click. Obviously, this technique is not always successful as it relies a lot on your capacity to guess the path of your subjects. And often, your subjects will actually alter their paths unexpectedly and get out of your in focus zone resulting in a misfocused shot. Obviously, you could stop down your lens (smaller aperture such as F8) for a longer zone of focus, but remember that this series is all about wide open shots! (click on picture to enlarge)

anticipation-focus-ii-lr.jpg

Leica M8 with 35mm Summilux Asph at F1.4, 1/350, ISO160