Adult and Community Learning
Air photographs for local and community history
How to use this tutorialThis tutorial will help you use air photographs in your own local study or project.
It is divided into 3 sessions:
Session one: which type of air photograph do I need?
Session two: how do I obtain air photographs?
Session three: how do I interpret an air photograph?
You will need to set aside about 20 minutes to work through each session. Each session includes interactive exercises, top tips, handouts and a quiz to help you reflect on your learning so far.
The case studies will give you inspirational ideas for how to use air photographs in group projects and there are also suggestions for further reading and links to other sources of information.
Introduction Air photographs are not just for archaeologists! Many new archaeological sites are identified and recorded from the air each year but air photographs also have a lot more to offer. They are a fascinating resource for anyone wishing to explore the history of their locality.
English Heritage holds over 3 million air photographs covering the whole of England from the 1940s to the present day.
This tutorial aims both to inspire and enable you to use air photographs in your own local study.
Learning outcomes
By working through this tutorial you will be able to:
- know how to select the images most suitable for your purpose
- find out how to access the photographs you want
- gain practice in 'reading' and interpreting air photographs
- explore exciting ideas about how to use air photographs in your project
SESSION ONE
Which type of air photograph do I need?Many millions of photographs have been taken of England from the air since the early 1900s. Fortunately, many of these have survived and are held in various collections across the country. The National Monuments Record, the public archive of English Heritage, holds over 3 million. It is therefore not unusual to find several tens or even a hundred or more photographs covering your area of interest. How can you ensure you get to see those which will serve you best?
Location and date are likely to be your first considerations but you may need to make a further selection to achieve the image detail you require.
Air photographs do not come as a standard format. Vertical; oblique; large-scale; small-scale; colour; and black and white views are just some of the options for you to select. How do you decide which will be most useful?
By the end of this session you will be able to select the most appropriate air photographs for your task.
Vertical or oblique views?
Vertical air photographs are taken immediately overhead using a camera fixed to the underside of the aircraft.
Oblique air photographs are generally taken by the photographer through the window of a light aircraft at angles of less than 90 degrees to the ground.
Click below to compare vertical and oblique views. Drag and drop the labels onto the photograph and see for yourself how the angle of the camera to the ground affects how an object will appear on the photograph.
This interactive opens up in a new window
Quick reference guide to the difference between vertical and oblique air photographs
Vertical air photographs: scale
When using vertical air photographs you will need to select the appropriate SCALE for your task
The SMALL SCALE (1:50,000) photograph on the left covers several kilometres of the Vale of White Horse in Oxfordshire. This scale of photography shows the topography, field systems, settlements and road pattern well, but it is difficult to pick out the detail of individual features.
The LARGE SCALE (1:7,500) photograph on the right shows clear details of the village and the airfield in Grove, Oxfordshire, photographed in February 1942. The corresponding area on the first photograph is shown in red.
Top Tip
LARGE SCALE = Small area covered but greater image detail
SMALL SCALE= Greater area covered but small image size
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What do we mean by scale?
Scale expresses the ratio of size between the photographic image and its corresponding reality on the ground. This is usually given as a representative fraction which avoids mentioning any unit of measurement.
For example:
| photographic scale of 1:10,000 |
1cm on the photograph represents |
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10,000cm on the ground
equally
1 inch on the photograph represents
10,000 inches on the ground |
Top Tip
Remember: the smaller the number after the colon the larger the scale of the photograph, e.g. 1:10,000 is a larger scale that 1:20,000. |
Oblique air photographs: high and low views
Oblique photographs are taken at an angle to the ground. The acuteness of this angle to the true vertical can vary.
If you compare these two photographs of Segsbury Camp, which lies just north of the Ridgeway near Wantage, Oxfordshire, you will see that the top photograph is taken at a greater angle from the vertical and includes the horizon. It is called a HIGH OBLIQUE and has a more distinct foreground, middle and background than the second photograph. This photograph is a LOW OBLIQUE and has been taken at a small angle from the vertical to record the archaeological excavation taking place during July 1996
Top Tip
HIGH OBLIQUES are useful for illustrating landscapes and providing context for individual features
LOW OBLIQUES can be near vertical and are great for showing details of individual features
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Other considerations
Weather conditions, the direction in which the camera is facing, the time of year and even the time of day when the photograph is taken, can all effect what you see - or what you don't see- on the photograph
Weather: cloud cover
Poor weather conditions and low cloud will affect visibility. Here, this vertical photograph is rendered useless by extensive cloud cover
Large Image
Timing of photography
 Low features in the landscape are revealed by the pattern of sunlight and shadow on their surface. The long shadows cast by the low winter sun help to pick out the earthworks which mark the site of the deserted village of Richardson, near Winterbourne Bassett,
Wiltshire. At midday in summer, when the sun is nearly overhead, these earthworks will cast little shadow and so remain virtually invisible. Large Image
Haze
Haze derived from industrial pollution limits visibility in this oblique air photograph
Large Image
End of Session
You will now have a clearer idea of how to select air photographs which best suit your purposes. However, do not worry if you are still not sure, as the staff who look after air photographic collections will be happy to advise you and it is often possible to request photocopies of the images for further selection at little charge.
Even better, if you are able to view the photographs online or visit the air photographic library. This will give you the opportunity to look at a wider range of photographs. As we have seen, according tot he conditions when the photographs were taken, certain features may or may not be visible.
Top Tip
When requesting air photographic coverage be selective to save time and money but try to view as many as possible of you 'best fit' air photographs taken under different conditions |
Have a go at this quiz to test your understanding of the material covered in session one.
Now go to session two which will show you how to request air photographs.
Case studiesIf you are uncertain whether air photographs will be useful to you, you may like to take a look now at these case studies for ideas. Otherwise, continue working through the tutorial and come back to this section later
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| Rodbourne |
Lancaster |
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| Exmoor |
Wantage |
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