A long time ago I was trained in digital photographic restoration and have dabbled about repairing old photos ever since. One of my good clients, Derby Cathedral, had been having a clear out in the crypt and found a wonderful old ink drawing of the cathedral tower in an old frame. Sadly the drawing was suffering from water damage and staining . The paper had also got very crinkled. My task was to restore this as best I could with a view to creating fine art prints. It took a while but here is a before and after of one of the drawings.
