Pre-focus Help

[pcfranchina]

How do you go about pre-focusing? How exact to you have to be?
Just curious how you guys do I for fast street shooting. By the time I raise my camera focus and meter, my subject is about 3 blocks away. Well maybe not that bad, but I’m definitely not that quick. Nobody wants to see a photo of the back of someone’s head.

Thanks!

 

[Finder]

How exact to you have to be?

That depends on the depth of field of the aperture/focal length in use. The object just needs to be within that limit.

 

[Jocko]

I tend to use hyperfocal focussing. Once you are in the situation in which you will be taking pictures (assuming you have a fully manual camera) meter and set the smallest aperture for a workable speed. Let's say you have a 50mm lens at F16. Focus on about 3.5m and by referring to the depth of field indicator you'll see that everything from infinity to around 1.80m will always be in focus, so you won't have to 🙂 You can now shoot without focussing. Obviously this can also be done at wider apertures, but with less depth of field.

Cheers, Ian

 

[markinlondon]

With a 35mm (or 40mm) lens you can zone focus quite effectively and never have to touch your focus ring even at f4. Wider apertures are trickier of course. Try to work out the depth of zone your subjects normally fall into and set the DOF scale accordingly.
Learning to judge the light is also helpful to avoid spending time metering, Meter each time the light changes significantly.You can rely on the film to give you a bit of slack if you err on the side of overexposure. Open up 2-3 stops into the shadows depending on the differential between light and shade.

 

[pcfranchina]

Thats what I figured, but I see some peoples street shots that have a extreem DOF. Maybe with an AF SLR its easier. I will keep tryen 🙂 Thanks!

 

[Warren T.]

Here's another strategy that you can use in addition to DOF. You can prefocus on a spot that is approximately the same distance from your intended subject. for example, your subject is on your left. You turn to your right and pick a spot that is the same distance from your intended subject. You prefocus on that spot, then you're free to wait until your subject has the right expression or pose. When you see it happening, or when your subject walks into the "zone", quickly bring the camera to your eye, frame the shot, and snap the shutter.

--Warren