Flash tips for snappers

Database News - Wednesday December 12, 2007

OPEN THOUGHT

Flash tips for snappers

DON SAMBANDARAKSA

I'm a reporter who takes most of my own photographs, so the graduation season a couple of months ago got me thinking on how few people use their flashes effectively. As a result, here are some tips I have noted over the years.

For most of my photos, I use flash in sunlight, and avoid using flash indoors if I can. This is very counter intuitive and admittedly having most of my prints used for relatively low-resolution newsprint does give me more leeway than otherwise. Here's why.

Using flash in sunlight helps to balance the light. Unless you are looking into the sun in the morning or evening, chances are that either the subject's face will be underexposed (too dark) or the background will be overexposed (too bright and with no detail), or both. Using flash will help retain detail in the face while at the same time retaining detail from being burned out in the background.

That is the theory. In practice, the extreme brightness of the sun here in Thailand means that even a large flash unit's range is severely limited. One trick is that since an even spread of light is not needed, it is safe to set the flash to its most narrow zoom setting (usually 85mm or 105mm on some zoom flashes). This will focus the light more tightly and, as long as the subject is not too off centre, will provide a few more metres of range. Even when the flash is too weak or the subject is too far away, using flash will provide a little sparkle in the eyes of the subjects.

However, what is worse in daylight is the flash diffuser. When taking flash pictures indoors, most of us know how ugly a hard flash's shadow is on a subject. Using a diffuser - usually a piece of plastic that goes over the flash - will reduce the flash's power but in return will give a softer shadow. Outdoors in midday, the already limited two or three metre range of a flash at full blast will be reduced to nothing with a diffuser.

The other trick is to bounce the flash off the ceiling or a wall.

In daylight there is no shadow to speak of, yet all too many photographers at the graduations were using diffusers in the day and a few still had their flashguns pointed skywards, perhaps bouncing it off the clouds.

However, perhaps the best way to take balanced pictures in daylight involves having an assistant with a reflector, usually crouching or lying in front of the subject reflecting light into his or her face. Great if you have an assistant, a moot point if you do not.

Indoors, using a diffuser is great. Reflecting the flash off a ceiling is also a good idea provided the ceiling is not too high and is white or grey. Wooden ceilings will give a yellow colour cast to the picture, but this is not something that cannot be compensated for with white balance settings or a bit of post-processing.

Whether I use flash or not indoors depends largely on the lighting. Not so much the amount, but the quality.

Even a good diffuser will leave a shadow, but the room lighting will usually be dispersed enough to not leave a hard shadow. However, my problems with most ballrooms is that the light is too warm or yellow.

Most cameras can compensate to a certain degree, but some ballrooms, such as the one which recently held the ICT Forum at Impact, was so yellow that skintones were coming out clipped. The picture of Wikipedia co-founder Jimmy Wales a couple of weeks ago is a case in point. Parts of his forehead were completely missing in detail even though the picture itself was not overexposed. In retrospect, using a diffuser and putting up with some shadow would have been preferable.

The other problem is that, depending on the lens, some cameras just will not focus in overly warm lighting. My Minolta 7D suffers specially at long focal lengths. In order to get a sharp picture, I often have to step down an extra stop to get the depth of field, which means a longer exposure - often tipping the balance in favour of using a hard flash just to get a usable picture

My rule of thumb is that if there is enough light for a decent image at up to ISO1600 at F4, I shoot without flash (1600 at F4 results in better pictures, in my subjective opinion, than ISO800 at F2.8). If the light is too warm or, worse, mixed (think tungsten light with a sunlit window to one side), then by all means use a flash - a shadow is better than a blurry picture with weird colour casts.

One very common mistake I see is people bouncing their flash off the ceiling and not checking its colour first. Brown wooden ceilings are not that bad, yellow colour cast aside, but the modern type of black matte with exposed wiring and air ducts means that very little light will be reflected, yet many photographers seem to point their flashes up without thinking.

The other thing to watch out for is the height of the ceiling. A small meeting room will give a decent soft bounced lighting effect at 50mm, but for larger rooms, the height of the ceiling often gives rise to "racoon eyes" where the forehead and eyes themselves cast a shadow. Stepping back and zooming in at around 70 to 100mm often works for most small to medium sized halls, or bouncing off a wall rather than a ceiling.

Shiny reflective backgrounds are not a problem, but one has to take these pictures at an angle rather than head on in order to avoid a flash reflection. But if you have to take them straight on, then two or even three stops of flash compensation is often needed to ensure that the subject is not under exposed.

So, before you take pictures during the festive season, spare a moment and think about where to point your flash or if you can get away without using one.

Bangkok Post