Imaging Projects

 

Building an Image Bank of Inscriptions

Aims

The imaging project for inscriptions developed out of an initiative to reorganise and catalogue Oxford University's squeeze collection and make it accessible as a research resource to the widest possible audience. The project draws its inspiration from the work undertaken at Michigan and Duke universities within the framework of APIS to create a unified database of papyrological resources including texts and, above all, images.

Methods

The requirements of an image database of inscriptions differ from those of a papyrological image bank in a basic respect - inscribed documents are in general much larger than written papyri. This makes it both possible, while retaining the advantages of the digital medium, and, indeed, necessary, in order to keep image sizes within manageable limits, to capture images at a lower resolution than the standard required for papyri.

During the initial experimental stage of the project images are being captured at resolutions of 150 dpi and 300 dpi. 150 dpi images are more than adequate for most purposes, but, in order to ensure that the images in the database remain useful for as long as possible, it has seemed better to set the higher resolution as the standard to be used in the second phase of the project, when representative corpora of images begin to be built up. Images are taken directly from squeezes using a UMAX Powerlook Pro flatbed scanner and a PowerMacintosh 8100. Images of inscriptions larger than the scanning area are stitched together from separate scans made using the same settings. Minor adjustments for contrast are made in Adobe Photoshop 3.0. Photoshop's Unsharp Mask filter has been applied to the derivative sample images available from this page, but not to the original scanned images. The project envisages acquiring a digital camera shortly, and it is hoped that experiments can begin with this during the autumn.

The primary images acquired for the database will be taken from squeezes. Because these are a secondary medium, the basic images contained in the image bank will necessarily be at least two stages removed from the originals that they represent. A squeeze, moreover, can represent only the inscribed face of an inscription. In a field of study in which mistakes can follow from inattention to the physical context and character of a document, these are potentially serious limitations to the scope of the database. Wherever possible, therefore, images of squeezes will be supplemented by photographs of the original monument. For studying the inscribed text itself, however, images of squeezes have considerable advantages, because they can be captured in controlled conditions and at a uniform scale. It is for this reason that they form the primary focus of the Centre's imaging project.

The quality of the image will depend naturally on the quality of the squeeze, which, in turn, will reflect the preservation of the inscribed surface. The sample images presented here are all taken from good squeezes, but in the case of OGIS 78, although the result is very useable, the difficulties of representing severely eroded surfaces are beginning to become obtrusive. It may be that image enhancement techniques will eventually have to be used to provide acceptable representations of particularly difficult texts. This is an issue that is at present under consideration.

Sample Images

The sample images of inscriptions listed below are organised according to geographical region. To view these images successfully, monitors should be set to show at least 256 levels of colour or grey:

 

Athens and Attica

IG, I

IG, II

Peloponnese

Central Greece

Aegean Islands

Asia Minor

Egypt and the Near East

 

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Comments from users are invited and should be addressed to csadinfo@sable.ox.ac.uk

Last updated by Charles Crowther on 7 February 1997