Digital SLRs exposed

The best photographs are captured by single-lens reflex cameras. Here’s how to make the most of your digital SLR

Gordon Laing, Computeract!ve 28 Apr 2008

Most amateur photographers have compact digital cameras but single-lens reflex (or SLR) models are growing in popularity.

Digital SLRs, or DSLRs for short, are physically bigger than traditional compact models and the major external difference is a removable lens, which can be swapped for models with, say, wider coverage or greater magnification.

DSLRs also offer full manual control for great creative options and are much more responsive than compacts, so no more delays or missed shots.

Inside the body, the photographic sensor may have a similar number of megapixels to the one in a compact camera, but it’s physically much larger - with around 10 times the surface area. This makes DSLRs more sensitive to light, which means much better image quality in dim conditions.

So, DSLRs have justifiably become the preferred camera for anyone who’s passionate about photography, and in this Masterclass we’ll explain how to make the most of their many benefits.

Staying focused
All DSLRs can auto-focus, but they don’t always get it right - and unlike compact cameras, a badly focused DSLR image can look much more blurred.

First make sure the viewfinder is set up correctly. Most DSLRs have a small dial next to the viewfinder which can be adjusted to suit different eyes. Adjust this until the numbers seen below or to the side of the viewfinder image are sharp.

In terms of auto-focus, all cameras are getting better, but many still get confused by off-centre subjects. The trick is to lock the focus. To do this, first point at the subject, then press the shutter release button halfway, as this will lock the focus. So with the shutter button held halfway down, recompose the shot, then press it all the way down to take the photo.

This will take some practice, but any mistaken photos can, of course, be deleted. It’s a useful lesson to learn, and works with any camera.

Controlling the amount in focus
Some photos have everything from near to far in sharp focus. Others may only have the main subject in focus, while the background is blurred. The range of distances that are in sharp focus is known as the depth of field, and it’s easily controlled on a DSLR.

The depth-of-field is controlled by an adjustable iris in the lens. As this iris gets smaller, the depth-of-field increases and a bigger range of distances becomes sharp. As the iris gets bigger, the depth of field decreases and a shorter range of distances becomes sharp.

Continued on page 2 >

See also: