environmental statement - Rotherham's Online Application for ...

Table 6.3: Photomontages
A photomontage is the superimposition of a rendered, photorealistic, computer generated
model of a structure (in this case wind turbines and associated structures) on to a baseline
photograph.
Baseline photographs were taken using a Canon EOS 30D digital SLR camera using a high
quality lens accurately calibrated to provide the equivalent of a 50mm lens on a traditional SLR
camera. All pictures were taken using a levelled tripod and using a high quality setting of 8.2
megapixel resolution. Each of the viewpoints presented in the ES is made up of several
photographs which have been stitched together using Adobe Photoshop software. During the
stitching process none of the photographs were distorted in terms of scaling.
At the time the baseline photographs were taken, co-ordinates of the viewpoints were recorded
using a GPS. Photographs were taken at 1.7m above ground level (i.e. approximately eye
level).
A 3D wireline model was generated of the development features, including turbines,
meteorological mast, access tracks and the sub-station. LSS v9.60 by McCarthy Taylor
Systems Ltd was used to generate the 3D model of the turbines and associated structures.
The model of the structures was rendered and lighting was set appropriate to the date, time
and orientation on which the photograph was taken.
A digital ground terrain model was generated in LSS v9.60 by McCarthy Taylor Systems Ltd
where the development was overlaid on top of it. Using world coordinates in the computer
modelling programme the photographic viewpoints were replicated such that a view was set up
looking at the structures from exactly the same location as where the baseline photograph was
taken from. The view from the model was then superimposed over the original photograph and
edited as necessary in Adobe Photoshop to give a final photomontage. Several known
landmarks in the far distance of the baseline photographs were recorded on site using a GPS
and used to check that the positioning and scale of the structures was correct.
Whilst every effort has been made to ensure the accuracy of the photomontages, it must be
appreciated that no photomontage could ever claim to be 100% accurate as there are a
number of technical limitations in the model relating to the accuracy of information available
from Ordnance Survey and from the GPS. For a detailed discussion regarding the limitations of
photomontages, please refer to Visual Representation of Windfarms – Good Practice Guidance
(SNH commissioned report FO3 AA 308/2).
In particular, it should be recognised that baseline photographs on which photomontages are
based can, at best, only ever be a „flattened‟ 2D representation of what the eye sees in 3D on
site. A photograph will never capture as much detail as the eye would see in the field, it
therefore follows that a photomontage can never truly capture the sense of perspective and
detail which would be possible in reality. Taking account of the inherent technical limitations in
producing and presenting photomontages, the photomontages for Penny Hill have been
produced according to best practice.
Therefore the wirelines are simply a tool to assist the Landscape Architect in his/her
assessment of effects. The assessment of visual effects in this section does not rely solely on
the accuracy of the photomontages. Professional judgement has been used to evaluate the
significance of effects.
An interpretation of monocular perspective could be obtained by viewing the photomontages
from a distance of 250mm curved through an appropriate radius.
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Penny Hill Wind Farm
Environmental Statement