Just wanted to share the good news that we (thanks to Mike Matthews and Scott Boroughs!) have completed all the video tutorials for the Basic EPMA window in Probe for EPMA:



Remember, this "floating" window is available from the File menu in Probe for EPMA and provides an easy to navigate set of buttons, Help file links and now video tutorials for those learning the software.

Of course you can all these videos plus many more on our Probe Software YouTube channel:

https://www.youtube.com/@ProbeSoftware

If you have any suggestions for improving this feature please let us know...

I would just like to point out that although the Remote server is very useful for creating custom applications for your JEOL or Cameca instrument, for example see the sample Excel spreadsheets in the Remote.msi installer, e.g.,

TestRemote.xls              - simple example of how to connect, and control your microprobe from Excel
TestReproduce.xls         - example of calls to test the spectrometer reproducibility on your microprobe
TestStability.xls              - example of calls to test your instrument stability over time
TestColumn.xls              - example to control the column functions on your microprobe

The above Excel files will probably need to be changed to Excel "macro" files with the extension .xlsm because the Remote interface utilizes the macro feature in Excel.  You can get started writing your own Excel macros to control your microprobe instrument by downloading the Remote server installer Remote.msi here:

https://probesoftware.com/smf/index.php?topic=88.msg315#msg315

One can also develop custom image acquisition applications as described here:

https://probesoftware.com/smf/index.php?topic=754.0

Finally I should note (the purpose of this post is), that although there is also a Deadtime_Acquire.xlsm Excel macro file that can be used to calibrate one's dead time constants, which utilizes the Deadtime_Calc.xlsx Excel spreadsheet designed by Paul Carpenter, I no longer recommend the use of these spreadsheets for the calibration of dead times on EPMA instruments.

The reason is that we now have a much more accurate dead time method which can handle the non-linear response of our counting electronics at much higher count rates as described here in this topic:

https://probesoftware.com/smf/index.php?topic=1466.msg11102#msg11102

This new logarithmic dead time method published last year in Microscopy & Microanalysis allows one to exceed the linear response model that previously limited us to ~50 kcps and allows one to obtain stable count rates to ~300 to 400 kcps using the new constant k-ratio method as shown in our M&M paper

https://academic.oup.com/mam/article-abstract/29/3/1096/7165464

If you do not have Probe for EPMA, the link above describes how to acquire the intensity data for this new dead time calibration, but if you do have Probe for EPMA, this new dead time calibration is very easy and fully automated, as described in the pdf file available from the Help menu in Probe for EPMA:

Decommissioned in early 2000 from Syracuse Uni. Kept in climate controlled storage under vacuum in Nashua NH. If interested contact mshishkov@gmail.com

I've decided it might be worth starting a new topic on this question because it's not completely intuitive how isotopes (atomic mass) are involved with our matrix correction procedures.  This will be a short post to start with but let's see how much interest there is.

To begin I noticed that Andrew Locock mentioned editing the atomic weight for carbon from 12.011 to 12.0107 in the Elements/Cations window and Probeman teased him a bit about that (though maybe Andrew had a good reason for making that change?).  After all as Probeman pointed out, the C13 ratios in diamond can vary considerably:

https://probesoftware.com/smf/index.php?topic=71.msg12766#msg12766

Now Andrew was only able to make such a change because Probe for EPMA recently (last summer) enabled one to edit the atomic masses from the GUI in both the Standard application (for standard compositions) and for unknowns (in Probe for EPMA) as described here:

https://probesoftware.com/smf/index.php?topic=40.msg12014#msg12014

but what effect does changing the atomic weights have in our quantitative matrix corrections? Well ideally it should have no effect as mass effects are essentially unobservarble at typical electron beam energies:

https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/abs/compositional-averaging-of-backscatter-intensities-in-compounds/0E233FBBB78BC96E8C14977DBC2B556B

and in fact in the absorption correction we normalize out mass effects by utilizing mass fractions with mass absorption coefficients and in the energy loss correction by utilizing mass fractions with mass thicknesses.  Though as noted in the paper above, backscatter corrections (and continuum productions) are not always handled appropriately (it's simply electrodynamics all the way down!).

In other words mass effects should normalized out in the absorption and energy loss corrections, and for backscatter corrections we should utilize Z based fractions (i.e., the Z fraction method described in our paper) for compounds. In fact this is how Davis Stowe at Gatan was able to get their "quantitative backscatter" method for determining lithium concentrations to work:

Stowe, Davd, et al. "Assessing the Accuracy of Lithium Contents Determined by Combined Quantitative Backscattered Electron and X-ray Energy Dispersive Spectroscopy Analysis." (2024): ozae044-085.

All that said, what effect does changing the atomic weights have on our quant results? Well assuming the standard and the unknown are both utilizing the same atomic weights, it should have no effect on the matrix corrections, but of course the reported mass concentrations will change.  That is to say that SiO2 with Si29 will have different mass concentrations than SiO2 with Si28.

Yes, that works perfectly!
Thanks very much for the tip - in the same window I then adjusted the molar mass to 12.0107.

Probe-for-EPMA is great software, made better by the excellent support.