Judging colour temperature 2

White balance adjustment of statue photographs

The first part of this exercise is to consider whether the above three photographs taken under different types of natural light would be improved if the blue or yellow casts in images 2 and 3 were adjusted to a more neutral tone.

It is relatively straightforward in Lightroom to make copies of these photographs and to adjust the white balance to reduce the colour casts. Image 1 is copied below together with the white balance adjusted versions of images 2 and 3.

I think that this adjusted version of image 2 is preferable to the original photograph taken in shade. The main reason is that the warmer colours are more visually attractive and seem more natural than the cooler colours for this stone statue.

For image 3, both the original orange tinged version and this adjusted version seem slightly unnatural. The strong shadows in the face and body shown from this viewpoint give the figure a more aggressive and unsettling appearance than the other two pictures.

I rather like the adjusted version as it seems visually stronger. The statue looks more vigorous and the bluish tinge makes the background seem slightly spooky. On the other hand, the relatively bright orange colour of the statue in the unadjusted version emphasizes its artificial nature, and this seems to weaken the visual impact despite the brighter colour.

Use and selection of white balance settings

I chose a modern sundial with the figures of King Edward 1st and his first wife Eleanor as the subject for comparing the camera's white balance settings. The sundial is an pale unsaturated greeny-blue colour, with letters and other details picked out in pale gold. This is located high up on a brick wall which has mottled colours of medium saturation red-orange, brown and grey.

Images in sunlight

Nikon 18-70mm at 56mm: Iso 200 f8 for 1/400th second

The camera's white balance was set at Automatic, Sunlight and Shade settings for the above three photos respectively. The time of day at 8 am in the morning was earlier than suggested in the instructions for the neutral sunlight. This was about two hours after sunrise. Unfortunately, there was no direct sunlight on my other visits to this location in the middle of the day.

I feel that the Shade white balance setting adds too much warm yellow to the scene. The pale gold lettering becomes rather lost against the body of the sundial. Furthermore, the brickwork becomes too bright relative to the muted colours of the sundial.

The camera's automatic white balance setting was very similar to the daylight setting in this case. The pale blue and gold tones of the sundial are in a better balance at this setting, and the colours of the brick wall are more muted.

Images in overcast light

Nikon 18-70mm at 55mm: Iso 100 at f5.6 for 1/60th

The above photographs were taken at 11.30 am with the white balance set to Automatic, Sunlight and Shade as before. The light levels are roughly 2 stops less than for the sunlight photographs above.

In this case, the Automatic white balance setting results in a distinctly blue cast relative to the Sunlight setting in the second photo. The Sunlight setting was the one closest to my visual perception.

I envisaged that the Shade setting may have been the most appropriate in these conditions. However, the shade setting is again rather too yellow for my taste. The delicate blue colour of the sundial is washed out to little more than grey. For these reasons, I would again select the photograph taken with Sunlight setting.

Images in the evening light

Nikon 18-70mm at 55mm: Iso 100 f5.6 for 1/60th second

These last three photographs were taken at 5 pm, just over two hours before sunset. After this the sunlight no longer falls upon the sundial, so I did not take any photos later than this. The light level is virtually the same as in the sequence taken in overcast light in the middle of the day.

The Automatic white balance setting has a blue cast which makes the colour of the main body of the sundial appear to be a mid-tone blue, rather than the pale blue that it is in neutral light.

The Sunlight setting is similar but the blue cast is slightly less. In this case, I consider that the Shade white balance setting provides the closest to the lighting conditions that I observed when taking the photographs.

Conclusions

It is interesting to compare the three photographs with the preferred white balance settings side by side for their other visual qualities.

• The photograph taken in direct morning sunlight (with Sunlight white balance setting) reveals the forms and textures of the figures, as well as the shadow of the bar giving the time of day that the photograph was taken. It is however quite difficult to make out the markings on the face of the sundial and other gold details.
• The photograph taken in overcast conditions (with Sunlight white balance setting) on the contrary, shows the markings on the face of the sundial and the other gold details as these shiny surfaces are reflecting the light. However the form and texture of the figures is barely distinguishable in the flat light.
• It is the photograph taken in the evening light which achieves a balance, as the shadows reveal the form and texture of the figures, whilst at the same time the reflections of the shiny gold surfaces are still quite clear. Unfortunately, at this angle of light the face of the sundial is in shade and it is not possible to read the time.

I also noted that the colour tones of these three photographs are reasonably consistent one with another.

I have found it a useful exercise to explore the effect of the white balance settings in different light conditions, and I realize that I should probably experiment more often with these, even with natural lighting situations.

It was also useful to see how the camera white balance settings come through into Lightroom software. I almost always take photographs in Raw with this Nikon camera, and the camera handbook contains a table of the colour temperatures for the white balance settings other than Automatic.

In Lightroom, where the camera white balance is set to Sunlight, Cloudy or Shady, the colour temperature and tint sliders in the Develop module in Lightroom are fixed for each of these settings e.g 4950K for Sunlight, 5550K for Cloudy and 7100K for Shady with similar fixed settings for tint. When set to Automatic, however, the colour temperature and tint sliders differ for each photograph.