The Survey:
As the area was very sensitive (an operational hospital) with public moving around the site we were directed to the project manager on arrival. After signing in and completing various administration tasks (Sometimes we are required to provide a H+ S report and operational manual, insurance etc.), we were shown the landing and take off site. This was well away from the general public and had restricted access, so we were confident that there would be minimal public traffic on site.
The Procedure:
When surveying building of this size (or any large area) it is important to find the correct starting and finishing locations in order to proceed in a logical manner around the building. It saves duplication the survey areas. As such we started on the west side of the building with the sun on our backs. As it was a very clear blue sky day (10mph max wind) we were working in a very high-contrast environment.
This has particular challenges especially in shadowy areas, away from direct sunlight. Here we must use either auto shutter and ISO settings or manually select them ourselves so that the client will see as much detail of the roof as possible. Moving around the roof area we concentrate the camera on various inaccessible locations taking care to zoom in on any particular details we feel the surveyor may interest in. There are generally all sorts of debris and maintenance issues, from plant growth to leaking gutters, rendering damage to slates missing and pointing issues. Notice the chimney stacks and their overall condition.
Sometimes the client isn’t present, (we just get a brief). so we need to make sure we cover details from every angle so that the surveyors report is comprehensive. As the building is so large it takes several batteries to complete the UAV survey and as per usual, once we had finished, the sun went in! Overcast days are so much easier for completing photography as you do not encounter such high contrast images.
Case study 2 – Kingston Hospital
Once all stills photography was complete we moved on to the video survey. This is conducted in 4K as per the client’s specifications. The great thing is the the 4k video is almost as good as the stills and the surveys can often see even more detail. They can even get stills from the video to highlight to their client any more signs of wear and tear.
The Conclusion:
As mentioned, this was quite a challenging environment in such a public space. During the course of the survey we had encounters with not only the general public, but also hospital management, concerned with privacy of the patients and noise. We had to reassure that no photographs were taken of individuals and we were only concerned with the roof structure. Privacy is of paramount importance and we respect all private locations.
