I am trying to run the "check all spectrometers for equivalent K-ratio" test on my microprobe. That is, verify
(1) that all spectrometers give equivalent K-ratios for a specific crystal and
(2) that the values returned are the correct values.
I have acquired Mg, Si and Al Ka counts on TAP on 3 spectrometers, on both oxide standards, and on a "good" reference material (NIST K412) which I am using as the test. I see 2 spectrometers give very close counts to one another and the 3rds is somewhat different. The question is, are the 2 correct and the 1 is not? For that I want to use CalcZAF to determine the theoretical raw-K-ratio for the 3 characteristic peaks, but when I "enter composition from database" for K412 (which I have as a std in the std database), and click "calculate" it shows the theoretical k-ratio relative to pure element std. If I click on an element (e.g. Mg), Element Properties box pops up, and Assigned Standard is a box, but it is greyed out and I cannot tell it to use my MgO as the std. I'm sure there is some way to tell it to use MgO but I don't see how. What is the solution?
Thanks for making this great software available.
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