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Digital Radiographs

The digital radiographs of all the known remaining fragments of the Antikythera Mechanism that were acquired by X-Tek Systems using their BladeRunner System are available for viewing and download on the website of Shaw Inspection Systems (formerly X-Tek Industrial).

The digital radiographs available include all the Main Fragments (fragments A to G) and the all the Small Fragments (fragments 1 to 75) and were obtained using X-Tek's BladeRunner CT system.

This system was configured with an X-Tek 225kV micro focus X-Ray source coupled with a 16" Perkin Elmer flat panel detector. The Perkin Elmer detector is 2048 x 2048 pixels square, with a pixel pitch of 0.4mm, or 400μm. In most cases the fragments were magnified by a factor of between 2.7 to 4.4 times, giving rise to typical scaled pixel sizes of about 75 to 46μm.

The main fragments were imaged at X-Ray potentials of 200, 150, and 100kV. The small fragments were only imaged at 150kV. For the purpose of uniformity, the radiographs presented here were all imaged at 150kV. The main fragments were imaged individually, the small fragments were imaged in small groups of up to 7.

The Perkin Elmer is a 16-bit detector and produces monochrome digital radiographs with 65536 grey levels. These have been converted to 8-bit images (256 grey levels), by scaling the contrast to best fit the dynamic range. These have then subsequently been compressed and saved as JPEG files. Where appropriate the images have been cropped, and radiographs of groups of images have been sub divided so that there is a single fragment per image. The image dimensions have been cropped to commonly used sizes (256, 384, 512, 768, 1024, 1280, 1536 etc), and deliberately kept in a square format. The filenames are self explanatory, and include the image dimensions.

The small fragments are those found in 2005 by Mary Zafeiropoulou in the Museum store. The history of how the fragments were distributed amongst the boxes is apparently not known. It is not absolutely certain that all the fragments belong to the Antikythera Mechanism.