Wave length regions/Spectral Range

sabki's picture

Dear All,

I have 1 Unit NIRs Equipment with spectral range/wave length region : 700-2500 nm and usually used for analyses of wood properties/wood quality for raw material pulp and paper.

Otherwise if I used other NIRs Equipment with spectral range :

Equipment A. 950-1650,

Equipment B 1600-2400

Equipment C 1000-2150.

How to mathching spectral for developed Model/NIRs Calibration with different spectral range?

Thanks & Regards,



hlmark's picture

Sabki - you've presented yourself with a very difficult problem. The reason it's so difficult is that since you are using different instruments, it's not only the wavelength range that differs, but many other of the instruments' measurement parameers as well.  The wavelength ranges you know about. The other parameters you don't know. It's not even clear from your description whether all the instrument use the same measurement mode, meaning whether they measure in transmisison or reflection? Do they use the same sample cell, or even the same kind of sample cell? Is the sample in the same relation to the instrument's optics, in the different instruments? Is the sample preparation the same, for all the different instruments? There are innumerable questions like those that can arise, and I doubt that the answers to all, if any, of them are avaialble.





td's picture

Dear Sabki,

I agree with everything that Howard told you.

If you are able to measure your samples in the full-range spectrometer and one or more of the restricted range instruments; then you can measure a set on the full-range and then when you do the calibration you can restrict the calibration to the ranges of the restricted range instruments and see if you can obtain a useful calibration. If any of these are good you could then test them on the appropriate instrument (you would need to follow a complete calibration experiment).

Alternatively, have you asked the manufactures if they have any experience of measuring your type of sample on their instruments? Most manufactures do have considerable experience and will be keen to help you.

Best wishes,