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Topic: Discrepancy between mMass versions outputs

I use two computers for analyzing my spectra : a PC version (3.12.1) and a Mac version (3.9.0 or 3.10) and I realized that the peak intensities are different depending on the software version.
Peak intensities with older version:
274.87044
1465.97979
3960.97661
1114.12729
Peak intensities with newer versions:
285.040261
1464.986799
3989.910637
1182.773638

This is very concerning as I am analyzing isotopes distributions!!!
Help please!!

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Re: Discrepancy between mMass versions outputs

Dear Rodrigo,
the peak picking algorithm is continuously developed and yes,  there might be some changes between mMass versions.

Anyway, calculated peak intensity strongly depends on the parameters set in Processing panels like baseline settings, smoothing and centroid height. The "real" intensity is calculated from acquired intensity minus peak baseline. Check the peak editor to see these intensities and compare the mMass versions you have.

I don't think this is only the case for mMass but for all the MS software as well - if you are interested in any quantification be sure to always use the same algorithm (software version) and method settings!

Best wishes,
Martin

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Re: Discrepancy between mMass versions outputs

Thank you Martin. I reinstalled the previous version and using the same baseline correction and I got very similar values:
185.4    184.3
942.4    941.2
1293.1    1291.7
513.3    511.8