The brief for this interesting project was to find and shoot scenes that meet the following descriptions:
1. A full-scaled image, with black, white and a full range of tones in between, all fitting nicely into the camera’s dynamic range,
2. A contrasty image, in which both shadows and highlights are right up against the edges of the scale,
3. A flat, low contrast image, in which there are no blacks or whites,
4. A high-key image, meaning one that is mostly at the bright end of the scale,
5. A low-key image, meaning one that is mostly at the dark end of the scale.
I then had to take a screen-grab of the Histogram, explain why it looks the way it does, and annotate it to show which parts of the histogram related to which tones in the image.
1. A full-scaled image.
The histogram shows a broad range of tones, with a few noticeable spikes relating to various parts of the image. If my understanding is correct, spikes occur where there are large areas of the same (or very similar) tones.
This was surprisingly difficult! I took a number of images, checking the histogram each time, but even in images that included patches of sunshine and shadow, the tones were fairly well distributed. I decided that a silhouette, or partial silhouette, was the way to go. As the histogram shows, there is a fairly low, even spread of midtones, but higher concentrations of very light and very dark tones. On the left, the histogram builds up right against the axis. On the right, there is a peak of very light tones, followed by a dip, then another sharp peak of pure whites, taking the form of a vertical line against the right axis.
2. A flat, low contrast image.
This one was much easier. Looking across to the Isle of Wight from the beach at Milford-on-Sea, I could see that as the sun started to set, the difference in tone between the sea, sky and cliffs was lessening. There were no obvious highlights, and in the low light, even the dark base of the cliffs looked grey, rather than black. The histogram shows that all tones within the image fall in the middle of the range.
3. A high-key image.
The most difficult part of this one is fighting the temptation to play around with the ‘Levels’ sliders in Photoshop! I can see that this would be a much punchier, high contrast image if the highlights were clipped slightly, and the shadows clipped significantly. However, the version above is how it looks straight out of the camera. As the histogram shows, the tones are concentrated on the right-hand side of the graph, showing that there are many more lighter tones than dark. An even more pronounced ‘high key’ histogram could have been produced if I had deliberately overexposed the image – however, this would have resulted in burnt-out highlights, giving an image with less definition, that was not so pleasant to look at.
I’ve fought temptation long enough... here’s the same image after a Levels ‘boost’, a clipping of highlights in the red channel and a slight increase in vibrance:
As can be seen, the contrast is much higher, giving the image more impact. I particularly like the way that clipping the shadows has strengthened the cloud reflections. The histogram is now much flatter and more evenly distributed:
The numerous peaks and troughs may be related to the way that the image has been processed. I was working in eight- bit mode, rather than 16-bit. When I adjusted the Levels, it is likely that some of the subtleties in the tonal range were lost or reduced in the process. Despite this, I still prefer this adjusted version to the original.
4. A low-key image.
Just as overexposing the high-key image would have resulted in a more appropriate histogram for this particular project, underexposing this low-key image would have given a sharper increase in tones at the dark end of the range, but would also have led to loss of detail in the shadowed areas. Rather than doing this, I have sacrificed gaining a ‘neat’ histogram in order to take a photograph that hopefully has more visual appeal. Again, I had to exercise some willpower by not making adjustments to the Levels or Curves!
I enjoyed this project, although it was harder than I thought it would be – particularly in the case of the high contrast image. I am now getting used to checking the histogram when ‘in the field’, and adjusting my exposures accordingly. In the long run, this will hopefully mean that I return home with a larger percentage of usable images, and that detail will be retained in the RAW file for both the light and dark areas of most images.
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