Exercise 4.3 – ambient artificial light

These images were taken during an evening walk through central London. They were taken between 7:20pm and 8:45 on an evening when sunset was at 7:03. Therefore, they show a transition through the ‘blue hour’ into full night-time.

All images were made with a Pentax K-1 and 24-70mm f/2.8 lens used in manual exposure mode. Most used ISO3200, apertures between f/4 and f/8 and handholdable shutter speeds.

I shot in RAW, so colour temperature decisions could be deferred until post-processing. I follow Rut Blees Luxemburg’s preference for embracing the real colour of the light source rather than attempting to correct it, so I have set a ‘daylight’ white balance (5500K) in all cases.

Post-processing was in Lightroom, where I adjusted overall contrast (and, occasionally, exposure) to fit my subjective memory of the scene. The typical adjustment is to open the shadows (moving the ‘shadows’ slider to the right) and tweak the ‘whites’ and ‘blacks’ sliders so that there is marginal clipping at both ends of the dynamic range. If this were a camera club competition, I would be tempted by local adjustments (grads and post-crop vignetting) but I have eschewed them for this exercise.

The main question with shooting night-time cityscapes is whether to use the artificial light sources as illumination (see Luxemburg or Brassaï) or as the subject (see Shintaro). I have attempted both approaches in this exercise.

As seen in the set above, in many well-illuminated spaces (street lit or internal), the emphasis is on quantity of light rather than its quality. Typically, there are multiple overhead light sources giving a soft, even, shadowless light. In Northumberland Avenue, the street lighting is bright enough that the illuminated theatre sign can be rendered without resorting to HDR.

In this set, the lighting is more directional. The floodlighting from the SNOG bus is intended to give a coloured ‘stage lighting’ effect while its internal lighting gives working light to the servers and, incidentally, illumination of the customers’ faces. With the couple reading the menu, there is overall street lighting but their faces are lit by the illuminated menu acting as a large softbox. In the bar image, there is no street lighting and the two figures are lit by very strongly coloured lights intended for dramatic illumination of the building.


In this image, shot in Trafalgar Square, the rather dim general light comes from the reflected floodlighting on the National Gallery but the womens’ faces are lit by their torchlight reflected from the pages of their guidebook.

In these wider views, the scene and the sky are dark or black and it is the light sources, and their reflections, which are the subject. Water is an obvious reflector, but I also used glossy paintwork on buses, taxis and other vehicles, and a surprising amount is reflected from dry roads and pavements which are ‘polished’ by use and seen at the right angle.


This is the classic ‘light-source-as-subject’ image, of Eros in Piccadilly Circus and the Coca-Cola ad behind him. I spot-metered the red of the illumination as a mid-tone and let the other tones fall as they will. My regret (and I will go back and re-shoot sometime) is that I set the shutter speed too fast (1/1250s) rather than closing the aperture or setting a lower sensitivity, which has caused a form of pixellation in the changing LED displays.

The final image is my favourite of the evening. The neon sign in the window is a picture element itself but also gives that glorious red internal illumination.


Exercise 4.3 preliminary – transition time

My main response to exercise 4.3 is a set of night-time images, taken in central London on 20 September. The images in this posting are a subset taken over a 10 minute period around sunset, between 7:01pm and 7:10. Sunset was 7:03, not that one would notice, given the heavy overcast. What is noticeable is the rapid change of light levels and the changing relationship between the intensity of the artificial light and the lightness of the sky.

Images were made with a Pentax K-1 and 24-70mm f/2.8 lens, used in manual exposure mode. There was minor tweaking in Lightroom, to adjust overall contrast rather than exposure.

All images were shot in RAW mode, deferring decisions on colour temperature until post-production. All images were set to ‘daylight’ (5500K) colour balance to enable a proper assessment of colour changes.

The interesting point is that, with the exception of the very bright ‘stage lighting’ floodlights on the SNOG bus, the artificial lights are insignificant in relation to the overall daylight levels. The first of the images used in Exercise 4.3 was taken at 7:20pm, 17 minutes after sunset, by which time the scene had darkened noticeably and it is the artificial lighting that dominates.