New research shines a light on how expert mapmakers at Ordnance Survey see the world differently

Apr 19, 2024

3 min


OS Remote Sensing Services survey team updating OS MasterMap using the latest aerial imagery (Image credit: OS)


  • Aston University psychologists worked with Ordnance Survey to assess how surveyors use 3D aerial images when making maps
  • Humans naturally assume light comes from above, but experienced surveyors can interpret visual cues to assess topography regardless of the light direction
  • It is the first time it has been shown that experience can radically alter natural human assumptions about lighting and could improve surveyor training.


Researchers at Aston University have found differences between experienced Ordnance Survey (OS) mapmakers and novices in the way that they interpret aerial images for mapmaking, which could lead to improved training processes for new recruits.


OS is well known for its travel and walking maps, but is also responsible for maintaining Great Britain’s national geographic database. Every time a building is demolished or developed, or a new road and path built, the map must be updated.


Aerial photographs are taken of the area that has changed, either from a plane or using drones, and expert mapmakers, known as remote sensing surveyors, will examine the images to identify change and accurately redraw the map of the area.


Image pairs are presented stereoscopically, one to each eye, allowing the remote sensing surveyors to see in 3D and correctly assess the topography, such as ditches, hills and hedges.


Led by Professor Andrew Schofield, a team from Aston University’s College of Health and Life Sciences, together with Dr Isabel Sargent, previously at OS, carried out a study to understand how remote sensing surveyors interpret the shadows and highlights in images.


The researchers asked six trained remote sensing surveyors and six novices to assess 10,000 stereoscopic aerial images of hedges and ditches, which had been heavily masked with image distortions.


The stereoscopic images the aerial surveyors use for mapmaking are usually taken on sunny days. The human brain is naturally wired to interpret light as coming from above. However, the light does not come from above in the OS aerial images, it depends on the position of the sun. In the UK, north of the equator, light comes slightly from the south, thus appearing to come from below in images viewed by the surveyors.


The researchers wanted to see how manipulating the direction of the light would affect the surveyors.


Professor Schofield and the team swapped the image pairs between the eyes in half of the trials, so that hedges might look like ditches, and ditches look like hedges. The images were also flipped vertically on half the trials, changing the direction of the light source.


Expert surveyors were found to rely on the stereoscopic cues – the difference in images seen by the two eyes – when performing the task.


Novices were more likely to rely on lighting cues – highlights and shadows – to judge the shape and relief of an object, and assumed, as is natural, that the lighting came from above.


With the manipulated images, this meant that novices frequently made mistakes. Experts were more accurate, even when the images had been turned upside down, and some had learnt to assume that the light source came from the south, or below.


This is the first time anyone has shown that the natural assumption that light comes from above, which is common amongst many animal species, can be changed through long term experience. The researchers say that it could be used to develop new visual training techniques for remote sensing surveyors. For example, intensive exposure to repeated, difficult images can improve performance via a process called perceptual learning.


Professor Schofield said:


“This is a very exciting result. Others have shown that the light-from-above assumption can be altered by a few degrees, but no one has ever found complete reversals following long term experience.


Dr Sargent said:


“This result will help Ordnance Survey to understand the expertise of their staff and improve surveyor training and procedures.”


Remote sensing surveyor Andy Ormerod, who worked on the study, said:


“This research proves that experienced remote sensing surveyors can see the world differently. Whereas non-surveyors are used to seeing the world from one perspective, our brains have learned to view the world as seen from aerial imagery.”


Journal of Vision DOI:10.1167/jov.24.4.11

Powered by

You might also like...

Check out some other posts from Aston University

2 min

Aston University economists say Prime Minister can reduce UK trade vulnerability with China visit

Greenland episode exposed UK’s lack of effective response to economic coercion from allies Research shows tariff retaliation would have cost the average UK household up to £324 per year Economists say China visit is “portfolio risk management” – diversification reduces vulnerability. The Prime Minister’s visit to China – the first by a British PM since 2018 – is an opportunity to reduce the UK’s vulnerability to economic coercion, according to new research from Aston University. A policy paper from Aston Business School’s Centre for Business Prosperity analyses the January 2026 Greenland tariff episode, when President Trump threatened and then withdrew tariffs on eight European countries. The researchers found that the UK had no good options: retaliation would have made Britain worse off, while absorbing the tariffs left Europe without credible deterrence. Director of the centre for business prosperity, Professor Jun Du, said: “The Greenland episode was a wake-up call. When your principal security ally threatens economic coercion, the old assumptions about who is safe and who is dangerous no longer hold. “The PM’s China visit should be framed as portfolio risk management – building diversified trading relationships that reduce the UK’s exposure to any single partner. Just as investors don’t put all their money in one stock, countries shouldn’t put all their trade into one basket. A UK with multiple strong partnerships is harder to pressure, whether the pressure comes from Washington or Beijing.” The research found that coordinated UK–EU tariff retaliation would have cost British households up to £324 per year – the worst outcome modelled. But the authors argue that Europe has untapped leverage elsewhere: the US runs a €148 billion annual services surplus with the EU, and mutual investment exceeds €5.3 trillion. Associate professor of economics and co-author, Dr Oleksandr Shepotylo, said: “Tariff retaliation fails because it hurts consumers and distorts the economy – the retaliator suffers similarly to the target. But Europe has cards it isn’t playing. Services, investment screening, and regulatory access are pressure points where Europe can respond effectively.” UK exports to China fell by 10.4% in the year to Q2 2025, with goods exports down 23.1% – the sharpest decline among major trading partners. The researchers argue that this closes off the UK’s largest alternative market at precisely the moment US reliability is in question. The paper identifies three priorities for UK policy: Recognise the permanent incentives behind US tariffs. US tariff revenue hit $264 billion in 2025. Trade negotiations alone cannot resolve revenue-driven policy. Build UK–EU coordination on non-tariff instruments. Services, investment, procurement, and regulation offer leverage that tariffs do not. Treat China engagement as portfolio risk management. Concentration in any single market creates vulnerability. Diversification is not about picking sides – it’s about resilience. Professor Du added: “The question for the Prime Minister is whether to use this breathing space to build resilience – or wait for the next Greenland.” To read the policy paper in full, click on this link:

2 min

Medication adherence: Why it matters and how we can improve it – public lecture by Professor Ian Maidment

Professor Ian Maidment is a professor in clinical pharmacy at Aston Pharmacy School His inaugural lecture will explain why patients struggle with taking medication and present possible solutions to the problem Professor Maidment is a former practising pharmacist and an expert in medication optimisation and management in mental health and dementia. Professor Ian Maidment, professor in clinical pharmacy at Aston Pharmacy School, will give a public lecture about his life’s work on 5 February 2025. In his inaugural lecture, Professor Maidment will reflect on his journey from a childhood in Kent to becoming a leading researcher in clinical pharmacy. After more than two decades working in the NHS, in community pharmacy, mental health, dementia care, and leadership roles, he joined Aston University in 2012. His research focuses on the real-world challenges of medication optimisation for patients, carers, and healthcare professionals. The title of Professor Maidment’s lecture is ‘Medication adherence: Why it matters and how we can improve it’. Every year, the UK spends nearly £21 billion on medicines. Yet up to half of people with long-term conditions do not take their medication as prescribed—a problem known as non-adherence. This has profound clinical consequences and significant financial implications for the NHS. Professor Maidment will draw on his experience to explore how factors such as medication burden and side-effects influence adherence, the challenges posed by conditions such as dementia and severe mental illness, the role of pharmacy in supporting adherence and why tackling non-adherence requires a system-wide approach. He will also offer practical solutions to one of healthcare’s most persistent problems. Professor Maidment said: “We need to understand why patients struggle to take their medication and then develop and test solutions that work well.” The lecture on Thursday 5 February 2026 will take place at Aston Business School. In-person tickets are available from Eventbrite. The public lecture will begin at 18:00 GMT with refreshments served from 17:30 GMT. It is free of charge and will be followed by a drinks reception. The lecture will also be streamed online.

3 min

New research partnership to develop biodegradable gloves from food waste for healthcare sector

Knowledge Transfer Partnership between Aston University and PFE Medical to develop a biodegradable clinical glove from food waste The gloves will provide a low-cost, convenient and sustainable alternative to the 1.4bn disposable gloves used in the NHS each year The innovation will reduce clinical waste and costs and help the NHS reach its net zero goals. Aston University and Midlands-based company PFE Medical are teaming up to create biodegradable gloves made from food waste for use in the NHS. They will offer a low-cost, convenient alternative to disposable gloves without compromising patient safety. More than 1.4bn disposable gloves are used by the NHS each year. They create large volumes of clinical waste which has both an environmental and economic cost. The Knowledge Transfer Partnership (KTP) project will develop a more sustainable alternative made from polymers derived from food waste such as orange peel, able to degrade naturally. The gloves will initially be for use during low-risk tasks such as ultrasound scans, rather than in more critical situations such as operating theatres. The gloves would be designed to not only reduce clinical waste and costs in the NHS, but also carbon emissions, helping the NHS reach its goal to be the world’s first net-zero health service. With most personal protective equipment (PPE) currently sourced from Chinese manufacturers, the goal is to develop a biodegradable glove that can be manufactured using a UK supply chain. The challenging project draws on Aston University’s expertise in sustainable polymer chemistry, centred at Aston Institute for Membrane Excellence (AIME). Aston University has one of the largest research groups of polymer chemists in the UK. The project will be led at the University by Professor Paul Topham, director of AIME, and Dr James Wilson, AIME associate member. The research team have chosen to focus on polymers from food waste in order to ensure that the final product can be manufactured sustainably. Most polymers are currently made from petroleum. Polymers made from food waste, ranging from fruit waste to corn or dairy products, have the potential for antioxidant and antibacterial properties if designed appropriately. The team will manipulate the polymer molecules so that they include the right monomers (the smaller units which make up the molecules) in the right location to achieve the properties they require. Critical to the success of the project will be PFE Medical’s commercial and clinical experience of taking new innovations into medical use. It will be the third KTP between Aston University and PFE, following on from successful projects to develop an automated endoscope cleaner, now in use across University Hospitals Birmingham NHS Foundation Trust (UHB). Professor Topham said: “At Aston University, we have a long history of working with industry, of translating fundamental research into solutions for real world problems. This project with PFE Medical provides us with that route, to take our science and engineering and make a difference to peoples’ lives. That’s exactly where, as researchers, we want to be.” Rob Hartley, CEO of PFE Medical, said: “Our previous KTP with Aston University was a phenomenal success, thanks to the brilliant team we had on board. I’m just as excited by this project, which is looking to solve an equally long-standing problem. If we can achieve our goal, then the implications are huge, going far beyond the NHS to all the other situations where people are wearing disposable gloves.” KTPs, funded by Innovate UK, are collaborations between a business, a university and a highly qualified research associate. The UK-wide programme helps businesses to improve their competitiveness and productivity through the better use of knowledge, technology and skills. Aston University is a sector-leading KTP provider, ranked first for project quality, and joint first for the volume of active projects. For further details about this KTP, visit the webpage: www.aston.ac.uk/business/collaborate-with-us/knowledge-transfer-partnership/at-work/pfe-medical.

View all posts