Chromatography Forum

Hi guys,

I am struggling a bit with the Class VP Software (v6.14) from Shimadzu.
I have different chromatograms, saved as .dat files, aquired with a fluorescence detector and a PDA (both datasets in one file). When I am accessing the files by just loading them into the software, everything is fine. But when I try to overlay chromatograms with the "add trace" function, there is no way to select which wavelength I want to be shown.
As an example:
- I open file A and I am able to choose wavelength 238nm (from the PDA data) to be shown
- I right click on the chromatogram and click on "add trace"
- There I can choose where to load the data from, I chose a file B
- In the same windows there is no a dropdown menu where I can choose which trace I want to have, here I can only choose the data from the fluorescencedetector (which i dont want), the spectrum max plot (which I also don't want) and sometimes there's a third choice saying "PDA, 254nm". Here I could not find a way to also select the 238nm wavelength to properly compare the chromatograms.
- Sometimes the option with "PDA, 254nm" is not even there, and I cannot figure out why

Anybody with the same problem? Or anyone with a solution?

Thanks in advance
Steff

You can try the following:
Locate "Multi" tab in "PDA Setup". Provide the wavelength of interest for comparison purpose. Save the method. Open data file and click analyse. You should be able to see the chromatogram of your wavelength in View-Gallery- Multi chromatogram
Sameway you can open other datafiles in this method click analyse once and then try to overlay. Hopefully this should solve the problem.

Best wishes,

Sivaraman

Thanks for the reply.
That actually works!
Another question: Some of the chromatograms I try to overlay are put in with their respective integrations (the markers to show where a peak starts and ends) and some of them are put in without these. So far that seems a little bit random, depending on which chromatogram I open first, which I find confusing, as the method should do it the same way every time, right?
Is there a possibilty to tell the programm, that it show all integration markers for all chromatograms or for none of them?