Neil,
Lively piece of wood mate sympathies from me with photographing some timbers are easy some mongrels. Your pic is soft focussed as well all of this happens to me unless I take charge of the depth of field trying to acheive at least f8 to f11 and then bracketing the exposure when I leave it on auto pilot it drops back to nearly wide open and no depth. The setting I use on my not very expensive Fuji Camera is labelled P that gives me control but auto focus as well. Try a white background in the end I use copy paper for mine.
Following your pens is fun. There was a lot of quilted and figured Sapele about last month here with the WWWood Show dealers very nice stuff like yours. Thanks for showing.
Kind regards Peter.