Understanding Calibration Sheets
Every spectrometer we ship comes with a calibration sheet listing the wavelength calibration coefficients (four floating-point values which can be used to derive the wavelength associated with each pixel on the detector), as well as a summary of the spectral lines (from mercury, argon, xenon, neon and other calibrated line sources) used to generate those coefficients.
However, it is key to understand that this calibration sheet only contains a brief and summative overview of the full data collected during our automated calibration and alignment process. In particular, the pixel values reported on the handout are “major peak locations” (nearest full-pixel). These pixel values are not sufficient to regenerate and validate the “Predicted λ” column of the calibration sheet.
In reality, our calibration software looks at the surrounding peak characteristics to predict and interpolate a more-precise “sub-pixel peak” location. It is this sub-pixel (fractional pixel) which is actually fed into the linear regression which generates our wavelength coefficients. Without having these fractional peak locations, you will not be able to manually re-generate the “Predicted λ” values to expected levels of precision. (You will arrive at a very close value, well within our accuracy specification, but it may not match the printed value to three decimal places.)