Hi,
I have noticed something strange:
Without touching the referencing or minimum and maximum aliased frequencies
I suddenly saw extension of the contours of my spectrum, showing aliased
peaks outside the normal spectrum boundaries.
We had a careful look at it, and it seems that changing the maximum aliased
frequency with only 0.001 ppm make the difference between a normal
contoured spectrum, and a spectrum with contours extended (duplicated) 4
ppm in 13C. I am wondering if there may have been some rounding error
somewhere that may have caused the maximum aliased frequencies to change a
tiny bit, and that that caused the spectrum contours to extend. I have been
adapting tolerances for spectra. One more thing: the extended contours
contain a peak that was picked on its normal position, but the aliased peak
box was not shown, only after the maximum aliased frequency was further
increased it would show it. This added to the confusion.
Regards,
Mattias
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