The hyperspectral imaging experiment went very well yesterday, 4 ‘scenes’ were imaged, a palate of pigment colour samples first, which we will hopefully be able to create a library from, which will aid in identifying pigments used in some of our manuscripts. We also imaged 5 Greek Papyrus fragments in glass, which have been damaged by inappropriate conservation techniques in the past. The fragments are completely blacked out, which leaves the text illegible. The hope is that with this technique, we will be able to create an image where the text is readable as it should be.
The most important item being imaged was the St Christopher woodcut mentioned in the last post. The watermark on the paper used for the woodcut will identify when the woodcut was produced, and, with a bit of luck, clear up the long running disagreement about its age. The final ‘Scene’ taken was of our incredibly fragile Haggadah manuscript, which is in deteriorating condition. The pigments in the manuscript requires very careful consolidation work, and from imaging pages in HSI, we should be able to identify exactly what pigments were used at the time the manuscript was written, allowing us to use the correct materials for consolidation.
The post processing of the data is a lengthy process, due to the amount of information captured for each image. Where a normal RGB camera will take information form 3 sources, the HSI camera takes 33. Information also needs to be taken from different sources to eliminate noise in both dark and light, and also to make corrections for the curvature of the filter used. All together, each single image can be created from almost 330 single images. That’s a lot of data to be prcoessed. When we have the results back in a couple of weeks, we will be sure to post them online.