It’s time to dive into the nuts and bolts of this subject. I mentioned in Part II that depth of field and focus were major challenges when doing macro & close-up photography. So this post will focus on these two inter-related issues, using a few examples.
The closer you get to your subject, the shallower your depth of field will be. If you stop down to small apertures your depth of field will increase accordingly. But that will slow your shutter speed, blurring anything that is moving even slightly. It will also bring your background into better focus, which may not be what you want.
But you can go beyond simply adjusting aperture. You can choose a point of view and composition that puts the background at the right distance to blur it in the amount you want (see examples below). Also, depending on the shape of your subject, camera position will directly affect how much of it is in focus. Positioning your camera becomes a key way to control depth of field and focus, even more so than in other types of photography.
Example 1: Recently, while in Organ Pipe Cactus National Monument, Arizona, I found the teddy-bear cholla cactus flowering with beautiful blooms. I wanted to show off both the color and the “guts” of the flower (its pistils & stamens), while at the same time giving a feel for the protecting spines all around. Flowers like this have some depth to them; they’re not flat-faced. So it’s tough to get close and still have all the petals plus the central reproductive parts all in focus.
So I positioned the camera at a sort of 3/4 angle to the face of the flower, so as to get the much of the central part in focus plus a few of the petals. I raised the tripod so it was slightly above the flower, so that a collection of cactus spines were at the right distance behind the bloom. I wanted them blurred but not too much.
The piece of blue sky beyond was a bonus, so I adjusted a bit so that it was to the side of the flower instead of right behind it. My point of focus was on the part that was closest to my lens. I had to raise ISO a bit so my shutter speed was fast enough to not allow the little breeze from blurring the flower.
Example 2: In the flower below, I thought the long hairy portion was very cool, so I shot from the side to get all of that in focus. I experimented with different apertures to get most of the bloom in focus while totally blurring the background (to put attention on the flower). I also positioned the camera very close to the ground to put the background as far away as possible. The wind again made me raise ISO to get a faster shutter speed.
Example 3: With the bee below I had to decide whether getting all the flower, including its petals, in focus was as important as a focused bee and blurry background. Since I was shooting a living subject, shutter speed needed to be fairly fast, and that naturally led to a larger aperture (which gave me the blurred background).
Would it be better if the front petals were in focus too? Sure. But other than taking several exposures and combining them, there was no practical way to do that. I go for simple over complex most of the time, even if it means trade-offs. By the way, I got lucky with that shutter speed of 1/60 sec. Normally you’d need something faster in this situation, especially hand-held.
So here’s the deal: think of moving the camera closer and further away from your subject as a way to control depth of field and the degree of blurring in your background. And think of moving your camera into different positions around the subject (side to side, low or high) as a way to not only get a more blurred background, but also to bring different parts of the subject into focus.
Next time we’ll go into some interesting ways to use macro and close-up photography in combination with other goals. I promise it will be something you just don’t see other photography teachers covering. Happy shooting!