Shooting at open apertures gives a beautiful creamy bokeh and blur to the background. But shooting at open apertures also comes with it's own set of difficulties too. These tricks will help you get sharper photos at open apertures.
1. Keep Your Subjects on the Same Plane.
When shooting at open apertures, keeping your subjects on the same plane becomes very important because there isn't very much depth of field. The easiest way to do this is to have your subjects feet all lined up, have them lined up shoulder to shoulder, holding hands, or have them sitting with their bums lined up in a row parallel to you. Having them touching in some way also helps to keep your subjects on the same plane.
2. Keep Your Distance.
Keep a good distance between you and your subjects, especially if you are photographing multiple subjects with an open aperture. Putting some distance between you and your subjects will give you a little more depth of field. Moving close to your subject will give you less depth of field.
3. Photographing Close Up?
If you are photographing a subject close up, pick an eye and focus on it. The eyes are the first thing we look at in a photograph and we expect the eyes, at the very least, to be in focus.
4. Keep Your Subjects as Far Away From the Background as Possible.
Keeping your subjects far away from the background does two different things. First, it will help to keep the background beautifully blurred. Second, the further your subject is from the background the sharper it will appear because of the contrast of sharpness between your subject and the beautifully blurred background.
For instance, if your subject is close to the background there will be little difference in sharpness between your subject and the background. But if your subject is far away from the background it will appear sharper in relationship to the blurry background.
5. Toggle Your Focus Points
Toggle your focus points when shooting at open apertures—especially if you are shooting at 2.0 or wider. Using the focus and recompose method at these types of open apertures leaves room for error and error is what we need less of at these open apertures.
6. Avoid the Widest F-Stop.
Avoid shooting at your lenses most open aperture. If you are using a 50mm f/1.4 don't pick 1.4 as your aperture, choose an aperture of at least f/1.6 instead. If you are shooting with an 85mm f/1.8, choose an aperture of at least 2.0 instead.
And if you aren't getting sharp images at those open apertures, choose a smaller aperture and then gradually work your way to shooting with more open apertures.
7. Find Good Light!
This might be the most important of all the tips. If you don't have good light, you camera and lens can't focus properly. If you don't have good light, you risk underexposing your shot. Underexposing your image introduces noise into the image as you brighten it and will make your subjects appear less sharp. Always look for good light and make sure that you are nailing your exposure in camera to ensure the sharpest image possible.