I’ve been lucky enough to have been asked to help a few friends with their photography. This usually takes the form of a walk with a pub at the end of it, where I claim my ‘fee’ – a sandwich. I usually get as much out of the day as they do whilst struggling to answer their questions.
One thing always becomes clear after 1/2 hour – everyone has skipped the bit of the manual which describes one of the most useful techniques in digital photography, namely focus and recompose. If you already use it – skip the rest of this post.
Focus and Recompose is a solution to that digital camera of yours deciding to focus and set exposure somewhere completely random in the frame, and frequently underexposing due to a bright background. Admittedly some cameras are worse than others – notably compacts.
It will also save you time twiddling around all those focus points in the viewfinder – something I can’t be bothered with to be honest.
Firstly set the focus area to only the centre of the LCD for a compact, or just the single centre AF point on a DSLR (you’ll have to get the manual out I’m afraid). That’s the end of the camera settings.
Now the camera will always focus on the centre of the image and set exposure accordingly so it’s wayward nature is at least under control.
Now you can point the central focus point at your subject and half press the shutter knowing exactly what it’s going to do.
Keep the shutter half pressed. Focus and exposure are now ‘locked in’ until you take your finger off the shutter or take the shot. This means you can now recompose the picture however you like, and fully depress the shutter.
Where you have a brightly lit background for a portrait, you can point the camera down slightly and focus on the torso, half press the shutter to get focus and exposure lock and then recompose.
Where this doesn’t work
By half pressing the shutter, you’ve now ‘locked’ the focus so don’t change the distance between you and your subject when recomposing. You’ll probably get away with it at wider focal lengths and smaller apertures as the depth of field will cover any differences in distance.
It probably won’t work that well with ultra fast lenses at maximum aperture, or telephotos as the depth of field may not cover the difference. For close up/macro work – don’t even try!
However as most people are using compacts or DSLRs with standard zooms with moderate maximum apertures it shouldn’t cause a problem.
Give it a try and plenty of practice – if it doesn’t work for you just set your focus points back to their default. If it does work for you you’ll never look back.
28mmf2 
When I first read the title, I thought it said “Focus and Recompense”….now that IS a useful technique….
Great post with some very good points that you explain very well. I don’t think I’ve used any focus point but the center since the first time I used an auto-focus lens. And I rarely use anything but center point (or weighted) metering. Two more decisions that you shouldn’t trust the camera to make for you.
Thanks for the comment – multiple focus points and scrolling a wheel round drives me nuts. It’s one of the reasons new DSLR owners get such disappointing results. When they see this technique it makes a huge difference.
Now if only I could get everyone to shoot in raw as well!