Have you ever wondered where you should focus when photographing a flower? If so, the first question you have to ask yourself is, “how much of the flower do I want in focus”? Then, depending on how much of the flower you want in focus, determine what f/stop you want to begin with. A smaller f/stop # means the lens opening is wide and you are letting in a lot of light. A wide-open lens results in a “shallow” depth-of-field or very small are of focus. When you are “stopped-down” to a larger f/stop #, less light is allowed in the lens and you have greater depth-of-field (or focus).
Looking at the rose on the left, the only thing I wanted in sharp focus was the pink rim at the top of the petal. I shot the rose with a 135mm lens and a 16mm extension tube at f/2.0 I placed the flower in this specific position so the petal I wanted to photograph would be close to my lens.
For the rose in the below, I wanted absolute focus on the center of the rose with decreasing focus as your eye moved away from the center and I wanted focus to at the outside of the rose to be non-existent. I used a 105mm macro lens at f/14 and I achieved my goal of a sharp center moving to very soft at the edges.
As you can see, the f/stop you choose is a key to how much of the flower you can get in focus. The next key is how close are you to the flower. The closer you get, the less focus you will have, regardless of the f/stop you use. That’s neither bad or good, it’s just important to keep that in mind because if your f/stop is set to f/11 or higher but you are still having problems attaining focus, it may be because you are too close to the subject.
So, to review, when deciding on where to focus it’s important to 1) decide what you want in focus, 2) choose a lens and f/stop that will hep you accomplish your focus goal, 3) vary your f/stop up/down for several images and 4) make sure that the focus you have obtained is clear/sharp (not soft or blurry).
In my next post, I will discuss how to get the entire flower in focus, if that’s what you’re looking for.