Problems about Detect Negative Peak

[rigol]

Dear sir:
I have some difficulty in seting detection inteval of Detect Negative Peak.In case the Detect Negative operation is active,I set Time A equals to 0.0,Let Time B equals to different values, and sometine these values differ only in 0.01,But we will get different results. Why is that?
Thank you !

[Daniel Mentlik]

Dear Daniel,
the images were not attached to the original post, most probably due to the image size. Please, send us both the images (with the graph and Integration table visible) and also the chromatogram file by email to support@dataapex.com . We will look into the matter.

[rigol]

OK,Thank you very much! I will send the email to support@dataapex.com .

[Daniel Mentlik]

Dear Daniel,
I have added the screenshots from your e-mail to the first post in the topic. Also, as other people may find this topic helpful in the future, I will copy the answer by Ivan Vinš here:

The recommended procedure for this chromatogram is to optimize the global integration parameters first using the Global Peak Width and Global Threshold tools.
In your chromatogram, the peak width is set to the low molecular weight components, the threshold is set approximately twice the suggested value. Then set the detect negative only to the interval where negative peaks should be detected.
The integration of negative peaks in combination with positive ones is sometimes difficult. In some cases it is useful to specify separate (discontinuous) integration intervals for areas, where the positive or negative peaks should be integrated and apply detect negative for the desired areas only.

Please note we are working on a more user-friendly behaviour of integrating alternating positive and negative peaks, which may be present in some of the next releases of Clarity.

Best Regards,
Daniel