In Manual mode, you control both the lens aperture and the shutter speed directly. The camera will still measure the light levels, but it will only recommend an exposure – it won’t change any of the settings itself.
Manual mode is useful in home photo studios and for still life photography where you’ve arranged the lighting carefully and have time to take exposure measurements, either with the camera or using a separate hand-held light meter (which can yield more accurate results in some conditions).
It’s also useful if you want to take a series of overlapping frames and stitch them together as a panorama. Here, it’s essential there are no exposure variations between the frames.
To set the exposure manually, turn the Mode dial to the M position. What happens next depends on the camera and how it’s set up.
On digital cameras with a single Command dial, turning the dial adjusts either the lens aperture or the shutter speed. To adjust the other, you hold down the exposure compensation button while you turn the dial.
On digital cameras with twin Command dials, one will adjust the shutter speed and the other will adjust the lens aperture.
- For more on your camera’s top plate, see Digital Cameras: what the manual doesn’t teach you
To measure the exposure using your camera, you need to look at the exposure display in the viewfinder or on the LCD and adjust the shutter speed and/or aperture until the marker appears in the middle of the exposure bar.
Handheld light meters have advantages in studios or in situations where you have your camera set up on a tripod. You can go up close to the subject and take meter readings from different areas to work out an average value.
Most handheld meters also include incident light attachments, which are translucent domes that fit over the sensor. These enable you to measure the amount of light falling on the subject rather than how much light it’s reflecting (which can vary according to the subject’s properties).
This is often the slowest but best way of measuring exposure, and is something that the exposure meters built into DSLRs can’t do themselves.
The handheld meter will quote a choice of shutter speeds and lens apertures, which you can then set on the camera using the controls we’ve already mentioned – it’s up to you how you want to balance the shutter speed against the lens aperture.
PAGE 1: Digital camera modes explained – Program Exposure mode
PAGE 2: Digital camera modes explained – Aperture Priority mode
PAGE 3: Digital camera modes explained – Shutter Priority mode
PAGE 4: Digital camera modes explained – Manual mode