Focus and Focal Length For Digital Photography

By 26th July 2015Articles

Digital photography is a great thing as a hobby. It is now an entirely do it yourself process as lengthy darkroom processes have been omitted by digitalization. With a little practice and effort you can take great pictures. There are certain things you need to master carefully when shooting with a DSLR if you want to take good pictures. This article covers a very important one – focus and focal length.

The sharpness of a picture depends upon focusing the lens correctly. The lens has many elements inside which can be adjusted by pushing-pulling or rotating the lens (depending upon the lens) for each particular distance between the subject and the camera. All digital cameras and lenses offer automatic focusing where the camera focuses the lens on the subject when the shutter is slightly depressed. But using manual focusing options you can be more creative. Move the focus mode switches on the camera and the lens to manual to start focusing manually.

While sharp focus of the subject is ideal for most photographs in some cases making the subject out of focus fully or slightly produces some very interesting effects. For example you can convey a dream like atmosphere in a photograph of a child if you can manage to create a soft focus which is a very slight off focus along with a very shallow depth of field. Depth of field can be made shallow by using bigger f numbers, lenses with long focal lengths (zoom or tele lenses) and by shooting from a distance from the subject.

A focal length of 45-50 mm is considered as the normal focal length as it offers the same view as the human eye. Lenses with bigger focal lengths are the tele lenses while the ones with smaller focal lengths are the wide lenses. Lenses with variable or adjustable focal lengths are the zoom lenses.

Wide lenses tend to stretch the image giving them a panoramic appearance. So use them for landscapes. It goes without saying that they will give you a wider coverage and bigger depth of field which you will need to shoot landscapes.

To shoot portraits and models use a moderate focal length like 70 to 90 mm. This will effectively blur out the background without making the depth of field too shallow and will give you crisp portraits.

If you want to shoot animals and birds opt for at least two lenses. You can go in for tele zooms as they will give you a big range of coverage. Ideal will be a 90-300mm and a 300-500 mm lens. This will let you shoot most subjects from a distance so as to not to disturb them or endanger yourself.

For shooting concerts and shows use medium zooms like 35-70 mm or 24- 70mm as they give you a bit of both wide and tele in one lens. In this way you do not have to change lenses in the middle of a program. You can miss vital parts of the program if you have to change lenses and you can also end up disturbing your neighbors.

Source by Dan Parker