A method of calibration of a dataset produced by an apparatus for scanning an object by causing incident radiation to impinge upon the object in a scanning zone and collecting spectroscopically resolved emergent intensity information of radiation after interaction with the object for use with a further apparatus for scanning an object, comprising the steps of: generating an apparatus condition specific calibration dataset of emergent radiation intensity information generated after interaction in the scanning zone of at least one standard object spectroscopically resolved into a plurality of frequency bands (b1, b2, b3, b4, b5; c1, c2, c3, c4, c5); populating a transferable database comprising a dataset of transferable data items of emergent intensity information for a range of possible component materials, each data item comprising emergent radiation intensity information for the material spectroscopically resolved into a plurality of frequency bands, and each data item remaining linked to the calibration dataset generated at the time it was produced; optionally repeating the foregoing step for a range of apparatus conditions; generating an apparatus condition specific calibration dataset for the further apparatus to be used comprising emergent radiation intensity information generated after interaction in the scanning zone of at least one standard object spectroscopically resolved into a plurality of frequency bands for an apparatus condition of the further apparatus to be used; generating a transfer function from the functional relationship between the calibration dataset linked to a data item and the calibration dataset generated for the further apparatus to be used by numerical comparison of the calibration datasets; for each transferable data item: applying the transfer function to the transferable data item to generate a dynamic data item adjusted to the further apparatus to be used; thereby populating a data register addressable by the further apparatus to be used with a dynamic dataset comprising a dataset of data items of emergent intensity information for a range of possible component materials each dynamically adjusted to the further apparatus to be used. generating an apparatus condition specific calibration dataset of emergent radiation intensity information generated after interaction in the scanning zone of at least one standard object spectroscopically resolved into a plurality of frequency bands (b1, b2, b3, b4, b5; c1, c2, c3, c4, c5); populating a transferable database comprising a dataset of transferable data items of emergent intensity information for a range of possible component materials, each data item comprising emergent radiation intensity information for the material spectroscopically resolved into a plurality of frequency bands, and each data item remaining linked to the calibration dataset generated at the time it was produced; optionally repeating the foregoing step for a range of apparatus conditions; generating an apparatus condition specific calibration dataset for the further apparatus to be used comprising emergent radiation intensity information generated after interaction in the scanning zone of at least one standard object spectroscopically resolved into a plurality of frequency bands for an apparatus condition of the further apparatus to be used; generating a transfer function from the functional relationship between the calibration dataset linked to a data item and the calibration dataset generated for the further apparatus to be used by numerical comparison of the calibration datasets; for each transferable data item: applying the transfer function to the transferable data item to generate a dynamic data item adjusted to the further apparatus to be used; thereby populating a data register addressable by the further apparatus to be used with a dynamic dataset comprising a dataset of data items of emergent intensity information for a range of possible component materials each dynamically adjusted to the further apparatus to be used. applying the transfer function to the transferable data item to generate a dynamic data item adjusted to the further apparatus to be used; thereby populating a data register addressable by the further apparatus to be used with a dynamic dataset comprising a dataset of data items of emergent intensity information for a range of possible component materials each dynamically adjusted to the further apparatus to be used.