When I first began doing landscape photography, I ignored using auto focus on my lenses and would use manual focus exclusively. Being that I was transitioning from a wildlife photographer to shooting mostly landscapes, I had assumed that the AF switch on my lenses had seen their last days. After a few more years and after second guessing my gear as I have upgraded over time, I realized what a mistake to just ignore auto focus altogether. I now use auto focus as much as I can and whenever I can.
Auto Focus for Wildlife
Now, you probably don’t need to use auto focus all the time and there are definitely instances where you must use manual focus. Here, we’ll first focus on a subject where auto focus really is necessary… wildlife. I’ve tried using manual focus for photographing wildlife and have mostly come up empty handed. Keep in mind that I have done it on very few occasions. Most who are trying to photograph wildlife likely want the animal engaged in some activity. Most large telephoto lenses have decent auto focus systems these days, but there are some budget-friendly lenses that may not be as swift. Trying to manually focus while tracking a moving animal is quite a task. Utilizing the auto focus in this case is simply a no-brainer.
Given you have the right light, using auto focus makes your success rate much higher. Now, when the auto focus begins to track and not stay put, it’s time to switch to manual. This usually occurs when there is not enough light to allow the auto focus system to track your subject properly. If you have steady hands, you can find the proper focus by manually rotating the focus ring on your lens.
Auto Focus for Landscapes
With more current cameras, it is easier to use auto focus for landscape photography. Many of these cameras have built in features that allow touch screen auto focus in live view. For me, this has been a life saver, especially when needing to focus stack an image. Many wide angle and zoom lenses have quick accurate auto focusing built in. The combination of quick auto focus and touch screen LCD makes stacking a breeze. You don’t always need to focus stack your images though.
I’ve found great success focusing about 1/3rd of the way into a wide angle scene. You want to be sure you are not extremely close to your foreground subject as well. I simply tap anywhere within the bottom third of the frame to get my focus. You may have to adjust when using longer focal lengths. If your camera does not have touch screen auto focus, don’t worry, you can still utilize live view to focus. One thing to take note of however, are auto focus points. Some cameras may only have a handful (usually older models), while others may have hundreds. These points are usually displayed as squares or rectangles in live view or through the view finder. Once you have decided where you want to focus, the square may turn green (on live view) or red (through the view finder), at least on Canon cameras.
Sometimes if you want to get as precise of a focus as possible and ensure that the areas you want are in focus, you can zoom in through live view. You can typically zoom in a maximum 10x via live view. I often use this method if the light is too low to use auto focus. When you zoom in that much, the scene may look blurry but don’t worry… it probably isn’t. Rotate the focus ring in either direction to find the least blurry version of the scene. When you found that perfect balance, take the shot and then zoom into the image via playback and make sure it is in focus. If you still have enough light, try using this method in addition to auto focus and see if they are both as sharp as one another.
Manual Focus for Low Light Photography
If you do any night photography, chances are you probably won’t be able to use auto focus. With the general atmosphere being extremely dark, it will be difficult and almost impossible to track a focus point using auto focus. In this case, I try to use the live view zoom in the method mentioned previously. This only works if there is something bright enough to see that you can zoom into and try to focus on… like city lights or the moon. The further away the better, but this could also be more difficult depending on your location. When using fast apertures however, foregrounds can appear soft which requires focus stacking. You can also try focusing to infinity on the lens (as long as you have a headlamp to see) as that will usually be the sweet spot.
Do you use any special techniques to achieve accurate focus for your photographs? If so, let’s hear them.