The technique described below works well if you use RAW to capture your pictures although most of it still applies to TIFF and JPEG capture. This article is a little technical but bear with it and your results will improve.

Whenever you determine the correct exposure on a digital camera the aim is to get the maximum possible detail recorded by the sensor – a bit like shooting black and white print film. The aim here is not to determine the density of the final image. This might mean that you have to ‘underexpose’ to make sure that all highlight detail is recorded. The biggest crime in digital exposure is burning out highlights because the lost information cannot be retrieved.

It certainly helps if you use the histogram when working out your exposure. Make sure that all of the peaks, no matter how small are in the visible histogram and not lost beyond the right hand side. Use the exposure compensation control to check. If you see a vertical line at the right hand end of the histogram you need to decrease your exposure. If you do not have a 'live histogram', do some test shots and look at the histograms they produce and change your exposure accordingly. Lost highlight detail cannot be brought back and you must avoid doing this.

The space on the right means that more detail could have been recorded

Once you have made sure that you have not lost the highlights you should then make sure that the histogram appears as far to the right as possible. This is known as exposing to the right and for technical reasons ensures that your camera records maximum detail. If there is a gap at the right hand end of the histogram you should increase the exposure even if it means that you leave a gap on the left. Sometime you might end up with an picture that is too bright but you cna put this right quickly in post-processing.

If you now print the resulting picture straight from your camera you may well be disappointed. What you will have produced is a good digital ‘negative’. You now need to tweak the image to make the picture that you want, using your computer. The point is taht you have recorded as much detail as possible. You may need to darken or brighten your image. You can do this either using your RAW capture program or by using the levels control which again uses a histogram. With certain images you might want a high key effect or a low key effect but it is in post-processing that you should achieve these effects.

Copyright © Greg Wright 2005 - All rights reserved