This document describes the steps required to make a Vertical Curtain from SEG-Y data in FMMIdwater.
Step 1 - Create a Project
Launch the FMMidwater (FMMW) application.
You should now see the FMMW User Interface (UI) in its initial state.
- Create a Project by either using keys Control + N or going to File > Create Project. Note that the Output Coordinate System for projects in FMMW must be unprotected, however, products can be re-projected on export.
Step 2 - Load your SEG-Y data
- Add your SEG-Y file by going to File > Add Sonar Files.
- Navigate to the SEG-Y data folder and select, and click Next.
- Set the coordinate system of the data you are importing, and cluck Finish.
- The newly loaded SEG-Y files will be listed in the FMMW map view and be listed in the Source Files are under Sensor.
- Convert the SEG-Y files(s) to GWC (Generic Water Column) format by selecting Tools > Convert Sonar Data > Select Files. The majority of the options for this wizard are set by the system, based upon extracted metadata within the files. The user is given the option to make changes on each page of the wizard.
- The GWC files are listed under the Midwater Node in the Source Files window, shown here:
- The sub-bottom image can be adjusted under the Signal Options Tab, which shows the histogram display. There are three options to adjusting a sub bottom image:
1) The composite slider at the bottom of the panel is used to set minimum/maximum thresholds for the type of signal that is used. Each end of the slider can be click/dragged to change either the minimum or maximum value of the threshold.
2) The center of the control can also be click/dragged to move the entire minimum/maximum the desired range.
3) You can also click the button to the right of the composite slider, which will launch a dialog for you to enter the minimum/maximum values numerically.As well, the locked bottom will cause these settings to be used for all currently loaded GWC files.
- Explore your data while moving your cursor along the data, note the updating position on the left side of the Status Bar display at the bottom of the screen. It displays the geographic coordinates, time, and depth (range) at which the cursor is pointing.
Areas of interest can be zoomed in by using left mouse button and dragging across the area of interest.
Hit the Zoom out button to return to the original image.
Step 3 - Export as Vertical Curtain
- Create a vertical curtain SD for Fledermaus by going to File > Export SD > Vertical Curtain.