I was experimenting the other day and found that this works pretty well:

Top Tip:

When taking black and white portraits contrast is important and so you need to get the light balance is correct, you need to find a good balance between the white highlights and the dark shadows. Try using a flash and reducing the exposure or ISO (This is the sensitivity of the film or equivalent in Digital photography). Experiment with these settings and you should hopefully find a good balance and hit just the mood that your looking for.

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Yes - ISO is the film Speed, with regard to traditional film, that is how quickly it reacts to light. A higher ISO will react more quickly to exposure to light, lower ISO will react more slowly and will also produce finer grain in your shots.

With Digital cameras the number represents the sensitvity of the Image Sensor, again the lower the number the lower the sensitivity.

Using a flash will often cause a portrait to "over expose" as the skin will reflect much of the light, therefore reducing the ISO will cause less light to enter the sensor and produce a finer grain of shot. Improving the exposure and detail.

Higher ISO is useful for low light situations where you still want a fast exposure - indoor sports for example, but the drawback is that in attempting to "absorb" more light you loose detail.

It is for these reasons that photographers studios are ofter very bright indeed. Low ISO and fast exposure is used creating sharp, criso and detailed shots - very important for portraits.

A very fine tip James!

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