Flash is a great benefit and a problem all at once!
Most people don’t realise two things about flash. First, the standard setting is nearly always too powerful. Second, the highlights resulting from flash are very distracting.
Working with flash power
Like all things in photography you need to think carefully about using flash. It is not simply click and move on. Most improving photographers are just beginning to make shots rather than snaps when they begin to see the quality and colour of light. So it is easy to miss some of the impacts that flash has on a subject. Here are a few consequences of a flash shot…
- An over-bright subject.
- Strong highlights with a tendency to wash out colours.
- Specular highlights that create sharp, bright spots that distract the eye.
- Bright foreground, dark background.
- Flesh tones strongly whitened giving a sick look to the face.
Each of these is almost always down to using too much power in the flash. So, the way to over come these issues is to do two things. Turn down the power of the flash and diffuse the flash so it scatters the light.
Turning down the flash is simple. You must find the setting that adjusts the flash power level. This is easy if you are using an off camera flash because the unit usually has a display and a dial or buttons to change the settings. On-camera (pop-up) flash is usually adjusted by finding a menu setting that turns the power up or down. You may need to consult your camera manual to find where that setting is found.
The key to getting the right setting for your flash is to understand how to change it. Most off-camera flash units are marked up so there is two stops of light on the flash. Normally if the flash is marked 1:1 then that is full power, and more often than not this is the default setting. You can usually turn this down by one third of a stop of light at a time. Each time you stop down the setting one stop you are halving the light it emits.
Pop-up flash units may not be marked so clearly. Some are marked [low – medium – high], others, particularly point and shoot cameras, may just have “full | half”. More sophisticated pop-up units may also be marked in the same way that off-camera flash units are marked. Which ever your flash is, you should practice with it so you have an idea of how powerful it is and how much the settings can change the impact of the flash.
The best way to get used to using flash and controlling the power is experimenting. However, the issue of nasty highlights is the other problem the inexperienced user often does not spot at first. Strong highlights raise the light levels so you can see the tonal changes in the colour of the surface the light hits. This helps to define the shape of an object. So, for example, a brighter top on a ball and dark shadows under it help to define the spherical shape.
If the light intensity is too high, particularly on reflective surfaces, the reflected light level will exceed the level the camera can cope with. The highlight then becomes blown out. The light is so bright in that area that it becomes a bright spot where all the detail is lost to pure white. Unfortunately such strong, blown out areas, are severe distractions. In the picture above, the small reflective points, called specular highlights, are also strongly distracting. So what can you do to avoid these nasty effects?
If your power adjustments are not working and you still have blown out spots or highlights then you should consider diffusing the flash. This makes a difference in two ways. The diffused light will scatter the light from the flash over a wider area. This effectively lowers the light intensity even further in the area of the highlight since the light is not hitting it from a direct focussed hard light from the flash.
Secondly, diffused light spreads the effect of the light. This makes it more likely to bounce off other surfaces nearby. These surfaces then become multiple mini-light sources. All these sources hitting your subject create a soft light which is much less likely to create specular highlights or very strong colour-destroying highlights.
So how do you do this diffusing?
For off camera flash I really recommend this superb diffuser…
For pop-up flash the options are not as easy. However, I recommend one of two options. I have successfully used ordinary white tissue paper sticky taped over the pop-up flash to both reduce and diffuse flash. However, while this works well, reducing the light by about a full stop, it is a temporary solution. Also, if you use the flash a lot the extra insulation may cause the flash to over heat. So, not for regular use.
My favoured options for pop-up flash diffusion are one of these three methods…
Great shots with flash…
Yes, like everything else in photography, to get good with it, you have to practice use of flash. However, first you need to make sure you can spot the highlights, specular highlights and over-powered flash. Once you know what you are looking for you can adjust your flash power.
The best way to gain control of your flash is reducing the power, or at least adjusting it. Also, the more you soften the harsh, hard flash light the less distracting and natural the highlights will be.
Whatever you decide to do to make your flash manageable do plenty of experimenting to gain control of the light. Don’t forget to Examine Shots Before Shooting Again – “Chimping” to check for highlights. The practice will pay you back in great, well lit shots many times over.
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