The challenges of representative Night Photography for assessment

Night photography for Visualisations and Landscape and Visual Impact Assessment (LVIA) can be required to aid the assessment of proposed lighting effects within existing views. In this article, Chris Hale shares an insight into our experience of undertaking effective night time photography.

There are many contributing factors to take into account, when undertaking night-photography for assessment purposes and it does differ from the artistic approach. The emphasis for assessment photography needs to be on accuracy and professional judgement.

Sensitivity

Development in or near to sensitive areas, and in particular, those protected by the International Dark-sky Association often require night time assessment. There are over 130 certified dark sky protection areas globally and these include several in the UK such as Cranborne Chase AONB, South Downs & Brecon Beacons National Parks. Government advice also provides detail on how to consider light pollution within the Planning System.

Whilst national methodologies or guidelines for daytime photography for LVIA and verified visualisation are well defined, there are other challenges when representing the human influences of artificial light in the landscape at night. What the eye sees or perceives, can be very different to what is captured in the camera lens. This difference in perception can be caused by numerous factors to do with how the eye sees and how cameras work. One example of this is often noticeable in dramatic photographs of the Aurura Borealis, although spectacular, they typically do not replicate the reality of the experience of witnessing the Aurora with the naked eye. This is because modern digital cameras can operate in lower light levels and capture a greater depth of colour than our eyes can detect.

Technical options

Taking night-time photographs that accurately represent what we experience ‘in the field’ is therefore a challenge that varies depending on the context. In urban or highly-lit areas where there is lots of artificial light available, the difference between what we experience and what is captured in camera must be judged so as not to be shown as too bright. In areas where artificial light is sparse, the situation could be reversed, temptation to over-expose the shot due to less light needs to be avoided. Particularly bright artificial lighting in a predominantly dark context can be the hardest condition to photograph accurately.

How accurate does the photography need to be? How will the images be presented, on paper or on screen? What will the end viewer need to see for the process as a whole to be considered reliable?  To create a successful image, we must remain faithful to the original scene as experienced ‘by eye’ on site.

For the landscape professional there are two main sources of guidance;

  • The Landscape Institute TGN 06/19 (Appendix 5) on night photography provides information on fieldwork techniques and equipment.
  • Scottish Natural Heritage provide basic advice; such as taking the photograph at least 30 minutes after sunset to retain some visibility of the landform whilst including existing artificial lighting such as streetlights for baseline comparison.

As for exactly what type of photograph should be used, how it should be prepared, and what should be visible in the photograph; there are a number of potential options available depending on the nature of the development and the subject matter.

For example, a series of photographs could be taken from dusk through to total darkness, but this limits the photography to one viewpoint per night. When taking multiple viewpoints for Environmental Impact Assessments, and being mindful of the cost and time associated with this, photographs could be taken in clear and fully dark conditions to demonstrate the effect of existing and proposed lighting only. It is always important to check with the determining authority beforehand which approach they require. The conditions need to be agreed beforehand.

Temporal factors

When proposed developments have a time limited artificial lighting presence, say during the operational hours of the development, photographs need to be taken within the operational timeframe in order to include the effects of existing contextual lighting . Perhaps the view incorporates, recreational or industrial areas only lit during certain hours or residential areas with private lighting or increased traffic movement. With moves towards net zero carbon there may be a tendency for artificial light to be switched off late at night which may also change the nature and timing of the baseline photography. All these factors are important, so rushing out at 3am in the middle of summer to get the ‘night-time’ photographs may not be the best idea, there is a lot to consider, in particular remembering what the purpose of the assessment is!

Accuracy and professional judgement

Whatever the night sky context for the proposed development may be, representing a night time landscape which accurately demonstrates what the eye can see in the view, needs to be carefully done and relies on professional judgement. Despite the poor ability of the eye to distinguish colours at night, the human eye is still able to distinguish some details, especially the horizon and sky.

What does the photograph show that the eye doesn’t see? Has the photograph missed subtle but crucial detail? Which of the multiple exposures is correct? Whilst avoiding issues such as aperture related starbursts effects, the photographer must use their skill and judgment to capture the night view according to what is perceived by eye whilst on location. Keeping a visual memory of the view and taking notes is important so that when you are viewing the images on screen later you can select the most appropriately exposed image for preparation for use. It is also worth remembering  that the printed image has more limitations compared with on screen viewing. The quality and cost of high-quality output of printed materials must not be underestimated.

Conclusion

Whist night photographs can be impressive and rewarding to capture, they must be reliable for assessment purposes and should not present a different impression of what is experienced in the field. Great care is needed, gained through experience and professional judgement when scheduling, preparing, taking and presenting night photography for assessment purposes.

How can we help you?

We have extensive experience in providing accurate viewpoint photographs for development proposals including night-time photography, photography and the preparation of verified views. Our work is used for use in visual impact assessment, to accompany Planning Applications or Appeals. For more information contact Chris.