Tuesday 11 October 2011

Auto-focus or manual focus?- tips for great photography

My Nikon camera has 51 separate focus points in which to place an object and the camera on auto-focus will use all, or any one or group of these I choose, to be the part of the image in focus. I normally work with just one focus point which I put over the eye of a person whom I am photographing, the part of the person, place or object most crucial in terms of sharpness. The auto-focus on quality cameras is extremely good and allows the photographer to think more about the quality of light and getting the exposure right.

In this picture I placed the focus point on the little girls nose,
getting the face and flower as sharp as I could

Only rarely do I actually set focus to manual, under low light conditions when auto-focus struggles, when something like a wire fence in the foreground is deceiving the auto-focus, very close-up photography, or I am using the hyperfocal distance in a landscape. Hyperfocal distance is the jargon for picking the point of focus in an image which enables you to maximise foreground and background sharpness and depends on the focal length of the lens, more on this in another blog.

Above Pott Shrigley on a stormy autumn day - I used the hyperfocal distance to get nearly everything in focus. I also use a very small aperture and slow shutter speed to make sure the depth of focus was maximised

Learning to control the focus point on your camera is very useful and this is actually what many non-professional cameras mean by manual focus, like Oona's Panasonic FZ38. In manual focus the photographer can decide on the focus in the very centre of the image using the little joy-stick on the back of the camera. The joystick operates the motor that changes the focus on the fixed lens. On a larger camera with inter-changable lenses there is a ring on the lens that you rotate to do this so you are directly moving the lens not the cameras focus motor.

 The little button in the middle when presses three times changes focus to manual
 The little joystick when pushed up and down changing the focus to be
nearer or further by activating the motor
on the fixed lens on this kind of camera
The ring on the left of the image is how removable lenses can be focused manually
and the little window tell you how far from the point of focus the camera is

So mechanisms might be different, but the purpose is the same, to get the vital bit of the picture sharp. Have a play with the focus setting this week. I had a great time playing with Oona's camera finding out how it worked!

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