Aggregate intensities in CalcImage

[Anette von der Handt]

Hi John,

I ran some maps that required a total of 9 elements (out of the 10 possible on my 5 WDS machine) and hence two map acquisitions. So rather than having one spectrometer sitting idle, I ran a map for one of the minor elements twice (once in the first map acquisition, then again in the second, same spectrometer).

When I want to crunch the maps through CalcImage (with aggregate intensity function on), it correctly recognizes that the second map is essentially already loaded in. Is there a clever workaround for me or should I simply run any aggregate intensity maps on two different spectrometers in the future (which has its benefits anyway)?

Thanks.

Edit by John: CalcImage doesn't support the aggregate feature currently. It is something that I need to find time to work on... in the meantime you could manually "aggregate" your x-ray maps prior to importing them in CalcImage by using the Surfer app- I think. Try it and let us know if that works.  If so, maybe I could implement that automatically during the CalcImage | Project | Create (new) Project Wizard process...

2nd Edit by John: The aggregate photon intensity method has now been fully implemented in CalcImage as described here:

http://probesoftware.com/smf/index.php?topic=41.msg2181#msg2181

[John Donovan]

I ran some maps that required a total of 9 elements (out of the 10 possible on my 5 WDS machine) and hence two map acquisitions. So rather than having one spectrometer sitting idle, I ran a map for one of the minor elements twice (once in the first map acquisition, then again in the second, same spectrometer).

When I want to crunch the maps through CalcImage (with aggregate intensity function on), it correctly recognizes that the second map is essentially already loaded in. Is there a clever workaround for me or should I simply run any aggregate intensity maps on two different spectrometers in the future (which has its benefits anyway)?

Hi Anette,
I just realized that you simply *cannot* have two elements with the same element, x-ray and spectrometer in Probe for EPMA (or CalcImage). Why? Because then there is no real way to tell them apart from each other, so that is that!

But you are correct, you can have duplicate elements in PFE and CI by using different spectrometers for the same element/x-ray pairs. But as I said before, although one can specify and calculate duplicate elements just fine in Probe for EPMA and CalcImage, unlike Probe for EPMA, CalcImage will not automatically aggregate the unknown duplicate x-ray maps for you as yet.  I am working on that this weekend.

The best thing for now is to acquire your standard intensities with the duplicate elements in Probe for EPMA, then set the Use Aggregate Intensities For Duplicate Quantitative Elements checkbox in the Analytical Analysis Option menu dialog. And then prior to loading the duplicate x-ray maps in CalcImage, simply "aggregate" the x-ray intensity grid files (.GRD) with duplicate elements using Surfer.

CalcImage *will* automatically aggregate the standard intensities and then apply them to the manually aggregated x-ray maps from Surfer for improved precision on the duplicate elements.

According to Aoife it is easy:

http://probesoftware.com/smf/index.php?topic=393.msg2123#msg2123

The statistics will fall through naturally because everything is in cps/nA units.

[John Donovan]

When I want to crunch the maps through CalcImage (with aggregate intensity function on), it correctly recognizes that the second map is essentially already loaded in. Is there a clever workaround for me or should I simply run any aggregate intensity maps on two different spectrometers in the future (which has its benefits anyway)?

Yes, duplicate elements need to be the same x-ray (or the photons can't be "aggregated"!), but different in the spectrometer, the crystal or both.

The good news is that the aggregate intensity feature in Probe for EPMA as described here:

http://probesoftware.com/smf/index.php?topic=29.msg387#msg387

is now implemented in CalcImage as demonstrated here:

http://probesoftware.com/smf/index.php?topic=41.msg2181#msg2181

This opens up some interesting mapping possibilities!

[Ben Buse]

Hi,

Returning to this, have 9 elements to map, one is a trace element which want to map on both passes. Guessing you could sum the two together in calcimage and then double the count time or average the two together and keep the same? Looking in calcimage it has a image maths option but doesn't save as prbimg files.

Is this just me?

Ben

[Ben Buse]

Thinking about it once you've done the 'align and crop' under convert in calcimage.

Then you want to sum the 1st and 2nd pass and sum the dwell time.

[John Donovan]

Hi,

Returning to this, have 9 elements to map, one is a trace element which want to map on both passes. Guessing you could sum the two together in calcimage and then double the count time or average the two together and keep the same? Looking in calcimage it has a image maths option but doesn't save as prbimg files.

Is this just me?

Ben

CalcImage treats aggregate elements just like Probe for EPMA does.  You can do duplicate elements on multiple spectrometers and then aggregate them, but you can't do the same element on the same spectrometer more than once.

Maybe you can combine the GRD files in Surfer, and edit the counting time in the PFE database using Microsoft Access?

I would try three passes and on the last pass acquire the trace element on multiple spectrometers like here:

https://probesoftware.com/smf/index.php?topic=41.msg2180#msg2180