Waters 2489 - Reviewing a Stored Spectrum; Subtracting a Spectrum

Scanning spectra 3-57
4. Press Enter to exit the information screen and return to the Scan choice
list.
Reviewing a stored spectrum
Once you have stored a spectrum, you can retrieve it for review from one of the
five available storage slots by selecting the Review option from the Scan choice
list.
To review a spectrum:
1. Press SCAN (Shift Chart Mark) to view the Scan choice list.
2. Press 4, Review.
Tip: When you select Review, you actually are retrieving the zero scan
and the sample scan that were stored as a pair.
3. Enter the storage slot number (1 to 3) of the spectrum you want to
review.
4. Press Enter. The message “Retrieving spectrum n” appears.
After a brief wait, the stored spectrum appears.
Once you retrieve a spectrum for review, you can view it graphically and
adjust the wavelength and AU ranges, if necessary. You can also run a new
sample scan based on the retrieved zero scan.
Subtracting a spectrum
Once you have stored more than one spectrum, you can create a difference
spectrum.
Tip: The current spectrum is the spectrum being subtracted from; the stored
spectrum whose slot number you enter is the spectrum being subtracted out.
To subtract and review the difference spectrum:
Rule: To subtract one spectrum from another, the starting and ending
wavelengths (λ1 and λ2) and the pace of both spectra must be identical.
1. Press SCAN (Shift Chart Mark).
2. Press 5, Subtract & review.