07. Using a Camera RunCoCo, University of Oxford http://runcoco.oucs.ox.ac.uk/ Oct 2012
07. Using a Camera
For Europeana 1914-1918 Roadshows
Summary of document:
- Position one camera above a table like a ‘copystand’ (on a tall tripod).
- Position another camera on a tripod for flexible movement.
- Take photos as a high quality .jpeg (between 2 - 5 megapixels).
- Try to minimise need for post-processing
- Consider how your items are lit.
Disadvantages of using a scanner to capture images include the slowness of the process, and that books or fragile papers must lie completely flat on the scanning bed, which may put pressure on the spine or damage pages. Using a digital camera you can capture objects of any size or shape, without damaging them. It is also generally faster than using a scanner.
On the tables where objects will be photographed you may set up a black cloth backdrop and table cover. You may also use weights to secure edges of cards or letters, and book-props (like the foam supports used in archive reading rooms) to position bound volumes like books or diaries.
Locate the cameras in a well-lit area and put each camera on a tripod or copy-stand by a table. For more information see “02. Setting Up the Venue”. and “11. Camera Settings” for Europeana 1914-1918 Roadshows.
Set up one camera above a table like a ‘copy-stand’
A copy-stand is normally the most efficient way of photographing flat objects. If this is not available some tripods allow the central column to be braced in a horizontal position for overhead shots.
Figure 1: Copy-stand. Figure 2: Camera mounted on copy-stand, Figure 3: Camera mounted on
separate lights positioned either side tripod with horizontal column
Position the camera on a tall tripod (1.5m high) with a horizontal bracket, facing the camera vertically downwards above the table. This allows you to quickly use it for taking photographs of flat objects (such as cards, papers). Alternatively a smaller tripod might be used on the table to enable a sort of ‘rostrum camera’ or copy-stand arrangement.
Mount the camera securely to the tripod. Use a spirit level to check the table is stable and level, both left to right and front to back, and to check that the camera is level. Remove the lens cap, if the camera has a neck strap remove it or keep it away from the lens. Although this sounds obvious, a lens cap can seriously damage an object if it is dropped later on in the workflow.
Position 2 or 4 lights of equal brightness and colour temperature (tungsten, fluorescent) on either side of the object. Professional lighting is ideal but if not available, desk lamps can be used. Check that the lights are at the same height and the same distance from where the object will be placed on the table, and pointing down at about 45 degrees. Switch on the lights, and check that light is not striking the lens.
Use a light-meter to check for even illumination. If the shadows are of equal density then the light is even. If you do not have a light-meter, by holding a pencil upright in the centre of the place where an object will be placed you can see the level and direction of any shadow from the lighting. Adjust lights if necessary.
If the object could be damaged by light or heat switch the lights off when they are not needed to set up the camera.
Place the object on the table and adjust its position. Non-fragile objects which have an uneven surface may be held flat beneath a clean sheet of glass. Adjust the height of the camera to frame the object and minimize the need for cropping the images.
Figure 4: Pencil on table showing shadows from the lights
Avoid using lower focal lengths (for example a wide 18mm setting) as this will introduce barrel distortion, so avoid focal lengths shorter than 35mm.
Figure 5: Setting a longer focal length, this lens offers a wide 18mm setting, which introduces barrel distortion
Set up one camera on a tripod for flexible movement
Place another camera on a different tripod. Having two digital cameras on two tripods (set at different heights and angles), with one or more photographers, will reduce delays when there are a lot of objects to digitise during the roadshow.
Lighting
Figure 6: Photograph taken using Figure 7: Taking a picture using Figure 8: Image taken using desk
built in flash. Note the hard a desk lamp and reflector lamp. Note the softer shadows shadows behind objects. around objects
Although there may be things you can do to set up the ideal conditions for each individual photo you take, be aware that the Roadshow can get very busy and that there may not be time to make considerable adjustments for each object.
Position the lamps to achieve the most pleasing lighting. Consider, how big is the subject? Do you want natural atmospheric lighting? Do you want to conceal or reveal surface detail?
Small objects (football size and smaller) can be illuminated with care using commonly available lights such as desk lamps. You can also use reflectors to shape the lighting on the subject.
Although most digital cameras have built-in flash units, their proximity to the lens makes them hard to modify and they often produce images with hard-edged shadows. To reduce the shadows and 'soften' the light a little on the surface texture try pointing the light at a large white surface, for example a small piece of white card. Or try to direct the light through a loop of light diffusing material, such as tracing paper, attached to the built in flash.
You may want to, or have to use available lighting, which although atmospheric, it is not always easy to control. It is essential that you identify the colour temperature of the available lights before starting so that you can configure your camera’s white balance if needed (see “11. Camera Settings for Europeana 1914-1918 Roadshows”).
If you want to pick out the surface detail of the subject you may have to use a 'bare' light source and direct it along the surface of the subject.
Take the photograph
When you are ready to take the picture, the camera’s self-timer or a cable release may be used to reduce the risk of camera shake;
1. Include the cloakroom/raffle ticket in the first photograph of the object. This is VERY important as it may not be possible to link the image to the relevant story otherwise;
2. Then capture the object without the ticket. Photograph the object from all relevant angles. It is better to have one too many pictures than missing something.
3. At regular intervals back up your camera’s memory card to the relevant space allocated.
As a camera is raised on a tripod it may be difficult to look through the viewfinder. Some cameras can be tethered to a computer. This also allows the operator to take control of most of the cameras functions from desk level. Before you remove the object, switch off the lights and check the quality of the file on the computer screen.
Make frequent back-ups of the files on your card. You may quickly transfer files between camera and computer using multiple memory cards and a card-reader. For more information see “05. Work-flow for Europeana 1914-1918 Roadshows”.
Acknowledgements
These guidelines have been created with close reference to Culturenet Cymru 2010 - Digitisation Guidelines, CD-ROM, Aberystwyth; and JISC Digital Media 2010 - How Do I Digitise Difficult Objects?, JISC, accessed 27 Feb 2011
http://www.jiscdigitalmedia.ac.uk/stillimages/advice/how-do-i-digitise-difficult-objects.
All images copyright, 1. is courtesy of kaiser-fototechnik and the others are reproduced with kind permission of Culturenet Cymru and JISC.
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