Intermediate Tutorial 8
This tutorial looks at the various flash modes and adjustments on your camera, which can ensure you achieve the best images for whatever ambient lighting conditions you are shooting in. Amongst the tricks to master is ISO adjustment and the use of additional kit, such as reflectors and diffusers.
Using a flash and overcoming lighting issues
As a photographer, you need to learn when to use a flash – and modern digital cameras help, because you have the advantage of being able to see the results immediately. So don’t be afraid to experiment and use flash for more than just indoor portraits.
How to use the flash
When stepping up to a DSLR or DSLM camera, one of the first things you notice is that, when shooting at night or in low light, the built-in flash doesn’t automatically fire.
This is because interchangeable lens cameras usually incorporate a ‘pop-up’ flash that must be activated. This means the camera decides whether to add more light based on a meter reading of the scene. With pop-up flashes, some cameras can be set to release and fire it automatically as needed. Others rely on you releasing it manually first:
Generally, you can use flash in any situation where the subject needs extra light, to improve exposure or eliminate shadows, such as when the subject is strongly lit from one side or behind. Of course there is always the option to not use flash at all, or to force the flash off – making full creative use of the ambient light.
Actually, there are several factors to consider and several flash control options on the camera, usually found in the shooting menu.
Shown below are the 1st level basic options found on the LUMIX G models:
Selecting the right type of flash
There are generally five main control modes:
Flash Forced On
Whenever the flash is ‘popped-up’ it will fire, irrespective of ambient light levels. Even with auto flash set, sometimes it may not fire as expected – typically, due to a small but prominent background highlight fooling the metering. Forcing the flash is also ideal to compensate for very strong backlighting rendering your subject effectively in its own shadow.
The technique called ‘Fill-in’ flash eliminates such shadow caused by bright sunshine; hence it is frequently used in wedding portraits to reveal greater detail in the bride’s dress or other shadow areas. It is also used in outdoor macro work and portraiture.
Flash with Red-eye Reduction / Anti Red-eye
When photographing people, direct flash commonly reflects off their retinas, creating red discs in the eyes. This phenomenon can be reduced or eliminated using this mode – a smaller pre-flash fires prior to the shutter opening, causing the subjects’ irises to close ahead of the main flash. These examples show ‘red-eye’ and after its removal (by software) – how it would have looked with ‘Anti Red-eye’ mode.
Enables a longer exposure (up to 1 sec) to be used to record ambient light as well as that from the flash. This allows detail to be captured in the shot’s foreground as well as its background. It is really useful when taking subjects that are close enough to be illuminated by the flash, yet still showing the background lit by natural light. Remember that your camera must be kept still throughout the exposure, so this mode is best used with a tripod.
Slow Syncro with Anti Red-eye
A combination of the above, for shooting people at night with background features that you also want to illuminate. Again, the camera must remain still – and likewise your subjects! Otherwise you may see a slight double exposure if subjects move while the shutter is open – which, incidentally, could be used deliberately for creative effect.
Flash Forced Off
For when you don’t want the flash to fire. This option only appears when using external flashguns. In the case of pop-ups, simply leave the flash down to prevent it from firing.
How much light will be added?
Every electronic flash device has a ‘guide number’ (GN) that approximates its light level and range, in feet or metres and usually measured at ISO 100. The built-in flash on the LUMIX G6, for example, has GN 8.3 at ISO 100 or 10.5 at its minimum ISO 160, meaning the flash will give the correct exposure with a subject 10.5m away, at the widest aperture of the kit lens. Of course, this is only a guide as different lenses and ISO settings will affect the results, so do experiment!
Flash too bright?
The distance from camera to subject is very important for obtaining good photographs when using flash. Subjects too far away will be underexposed, as the light intensity drops away, while subjects too close will be ‘washed out’ – overexposed, as in the first example below – the light intensity is too much.
The third example shows correct flash intensity; your camera’s metering will adjust flash output to try to achieve this, although you will usually have the option to adjust the flash intensity manually +/- three stops in the camera’s set-up menu.
So, again, do experiment and you should find you can ‘tune’ the results to your preference.
Using lighting aids
There are a number of ways you can influence the effect flash has on your images, and there are many lighting aids that help control, not just the light from a flash, but also ambient light sources.
Many external flashguns – and some pop-up flashes – have a tiltable head that can be positioned so as to direct the flash off another surface. This ‘Bounce lighting’ method creates a softer effect on your subject compared to a hard direct light – as you can see on this image of a sleeping child.
A simple reflector can also be used to direct the flash, to increase its effect on a particular part of a scene.
Often this will be a ‘bounce’ reflector fitted directly to the flash, used to increase the spread of the light and also to produce a ‘softening’ effect.
Different coloured reflectors can also alter the tone (colour temperature) of the light, for example gold reflectors are often used to give subjects a warmer skin tone.
For a more directional light a ‘Snoot’ type of hood on the flash concentrates light to a particular area, while a diffuser, placed in front / over the flash will spread the light giving an overall ‘softer’ illumination.
As an alternative to flash, many photographers also employ handheld reflectors for use with strong directional daylight; small ones are great for still life, or macro work in the field.
The majority of the aforementioned techniques can be utilised for the built-in flash although the latter mentioned hoods and reflectors may well work better with an external flashgun.
Adding an additional flashgun to your kit will open up lots of creative possibilities, and we explore those a little closer in our Advanced Flash module.
Weather conditions and ISO
The weather plays an important part in photography – interesting and exciting images can be captured under a wide variety of conditions.
And it is not just light levels that matter, but also its quality or ‘tone’.
- Brilliant light – a bright sunny day – is not necessarily ideal, as it can lead to bright areas being washed out while shadows seem too dark.
- Flat light – with cloud cover diffusing the sun’s rays – actually reveals more detail, because its lower luminance gives a more even exposure level over wider areas, however it can lack drama.
- ‘Hard’ light means much higher contrast than ‘soft’ light, and often seems to fall on a subject from only one direction, as in this first example. Soft lighting, the second, has a subject seemingly illuminated from various directions – with a corresponding lack of contrast:
With less light you may be restricted to longer exposures, wider apertures and higher ISO. These can often be turned to your advantage – just remember to be mindful of shutter speed when shooting hand-held.
Although using flash can transform your pictures, remember that modern cameras can produce incredibly detailed images at high ISO. So sometimes, particularly if your subject is quite distant or the scene is too wide for even flash cover, you can get the result you want by setting the sensitivity much higher.
The LUMIX Advantage
LUMIX G cameras feature an Auto Exposure Compensation Flash mode – with this enabled, you can quickly apply exposure compensation to your flash photography, either with the built-in flash or a more powerful separate flashgun.
Experiment with using flash to compensate for strong backlighting, remembering that it will reach only so far. Find a backlit subject and try varying camera distance as well as flash intensity.
Not sure what something means? Read our glossary