How do I keep a subject sharp when it’s moving toward or away from the camera?
Asked 5/9/2011
1 views
2 answers
0
When I shoot events or action, front-on or rear-view angles can be very expressive, but I struggle to keep focus when the subject is moving directly toward me or away from me. If I use single autofocus, the delay between focusing and releasing the shutter is often enough for the subject to move out of focus, especially when shooting wide open. Burst mode alone doesn’t seem to help because the focus plane keeps changing. I’ve also tried manual focus and anticipating where the subject will be, but I often miss. What techniques or camera settings work best for this kind of shot?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
15y ago
2 Answers
16
This is a classic use-case for continuous autofocus (AF-C). Nikon uses that term, Canon refers to this mode as AI-Servo.
This does not guarantee anything though, just improves your odds depending on:
- Which camera you use: Advanced cameras have predictive-autofocus which calculate the speed at which a subject moves and keeps moving the focus in that direction. This is to be used in combination with burst mode.
- Which lens you use: Brighter lenses can focus faster even if you shoot at a smaller aperture. Different lenses also focus at different speeds for plenty of other reasons.
- The speed of your subject: Obviously!
- The contrast of the subject: Contrast is required to focus and the more contrast the easier it is to focus, so the lens can focus faster.
- Shooting aperture: A small aperture gives you more depth-of-field so focus can be less precise. Keep in mind if it is too small, the shutter-speed will cause the subject to blur.
- The focus point: In almost all cameras the center focus-point is more sensitive and can focus faster and with less light.
Originally by user1620. Source · Licensed CC BY-SA 4.0
user1620
15y ago
0
Generated from our catalog & community — verify before relying on it.
Use continuous autofocus tracking rather than single-shot AF. On Nikon this is AF-C; on Canon it’s AI Servo. This mode keeps adjusting focus as the subject moves, and on more advanced cameras predictive autofocus can estimate the subject’s movement and improve your hit rate, especially when combined with burst shooting.
A few things affect how well this works:
- camera AF system: better bodies track motion more effectively
- lens focus speed: some lenses focus faster, and brighter lenses often help AF performance
- subject contrast: higher-contrast subjects are easier to track
- subject speed: faster movement is harder to keep sharp
- aperture: stopping down somewhat gives you more depth of field and more margin for error than shooting wide open
If you have room, one practical technique is to move forward or backward with the subject to reduce changes in subject distance while using continuous AF. Just be careful of your surroundings.
If your camera lacks good continuous/predictive AF, this kind of shot is much harder and manual focus timing becomes much less reliable.
Recommended products
UniqueBot
AI15y ago
Your Answer
Related Questions
Why won’t my Nikon D5100 keep shooting and tracking focus on subjects moving toward me?
Will changing subject size when using a focus rail affect focus stacking?
How can I get sharp photos with a DSLR that has only a few central AF points?
How can I get more keepers with a 50mm f/1.8 when shooting moving street subjects?
How can I enjoy an event and still take photos without missing everything?