SeaDAS Spectrum View

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avmehta
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SeaDAS Spectrum View

by avmehta » Thu Aug 04, 2022 10:14 am America/New_York

Hello,
I am using SeaDAS 8.1.0 GUI for analysis of OLCI Level-2 Rrs. I have two collocated images for which I am trying view spectra. Earlier, I could compare spectra from collocated images (referred to as Master and Slave) but that feature is no longer available it seems! Is there a way to have separate Rrs spectral for the two images displayed in the same window?
Thank you.
Amita

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OB SeaDAS - knowles
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Re: SeaDAS Spectrum View

by OB SeaDAS - knowles » Thu Aug 04, 2022 12:05 pm America/New_York

I think what you are asking about is the location of the Spectrum View tool. For SeaDAS this tool is located in the Analysis toolbar, or can be found in Menu > Optical > Spectrum View. Another way to find a tool is to type the tool name in the search field at the top right of SeaDAS 8

For any file which is identified by SeaDAS as containing a spectral component in the data, the Spectrum View tool can display all the relevant bands in a single plot across the spectrum.

To determine whether SeaDAS has identified a particular band as containing a spectral component, for an open file, in the File Manager right click on a band and select "Properties". In the Properties window for the band, if the field "Spectral Wavelength" contains a value then SeaDAS can use this spectral component in tools such as Spectrum View. If it does not contain a value, you can manually edit "Spectral Wavelength" if you wish.

avmehta
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Re: SeaDAS Spectrum View

by avmehta » Thu Aug 04, 2022 2:24 pm America/New_York

Hello,
I know where the 'spectrum view' is. The problem I have is with the filtering option! It is not the same as it was in the previous version! Earlier I used to be able to choose to plot Rhos or Rrs
with different symbols (for example see the attached SpectralView1) -- now it just plots all spectral components and can't tell which one is which (SpectralView2)!
Thanks.
Amita
SpectralView1.png
SpectralView1.png (62.65 KiB) Not viewed yet
SpectralView1.png
SpectralView1.png (62.65 KiB) Not viewed yet
Attachments
SpectralView2.png
SpectralView2.png (456.1 KiB) Not viewed yet

OB SeaDAS - knowles
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Re: SeaDAS Spectrum View

by OB SeaDAS - knowles » Tue Aug 16, 2022 2:04 pm America/New_York

I don't believe the problem you are experiencing is associated with any difference between SeaDAS 8.2.0 and the prior SeaDAS 7 versions. The problem with your last plot is likely that you don't have your bands grouped together into folders in the File Manager.

See the two attached images. The bands need to be grouped into folders in order for Spectrum Plot to understand that particular bands should be grouped together in the plot.

Grouped bands
grouped.png
grouped.png (59.86 KiB) Not viewed yet
Ungrouped bands
ungrouped.png
ungrouped.png (56.76 KiB) Not viewed yet
To group the bands you can right click on the filename in the File Manager, then select properties, then specify the grouping in the field "Band Grouping" as a colon delimited string. For instance "Rrs:rhos:nLw"

Files such as the NASA OBDAAC level 2 files, can be loaded and recognized by SeaDAS, and predefined band groupings will be applied by default. Files which don't have a reader which specifically groups the bands, may or may not group the band depending on the metadata of the file and how the file is imported into SeaDAS.

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