McIDAS Learning Guide
Version 2015

## Satellite Imagery - Using Briefing Windows

In addition to displaying loops in the Image Window, you can also create briefing windows to view saved loops. Each briefing window can display a frame or loop different from those currently shown in the Image Window or other briefing windows.

In this exercise, you will display a sequence of GOES-7 visible and infrared image with the same geographical coverage. You will then create two briefing frames, so that you can view the images at the same time.

1. Erase the graphics in frames 1 and 2.
Type:  ERASE G 1 2
2. Display the first GOES-7 4km Visible image area on frame 1, centering the image on earth coordinates 35° N and 75° W. Use the SF= keyword to automatically display the frame.
Type:  IMGDISP GV4.1 1 LATLON=35 75 SF=YES
3. Display the next two GOES-7 visible images on frames 2 and 3, centering the images on coordinates 35° N and 75° W.
Type:  IMGDISP GV4.2 2 LATLON=35 75;IMGDISP GV4.3 3 LATLON=35 75
4. Display the three GOES-7 infrared images, which begin in position 4, on frames opposite the GOES-7 visible images. The repeat factor (3) loads all three images with one IMGDISP command.
Type:  IMGDISP GI4.1 OPP LATLON=35 75 REPEAT=3
You are using the same coordinates, 35° N and 75° W, to load the images. The repeat factor 3 displays three images in sequence, on frames 4, 5, and 6.

5. Change the dwell rate, set the loop, and loop the images.
Type:  DR 5
Type:  LS 1-3
Press:  Alt L
You should see the loop of the GOES visible images on frames 1 through 3.

6. Toggle to the opposite loop to compare the images. Then stop the loop.
Press:  Alt O

You should see the loop of the GOES-7 infrared images on frames 4 through 6.

7. Create a text file that will be used to create briefing frames.
Save the file BRIEF.SYNC in your \$HOME/mcidas/data directory as a text file.
8. Create two briefing windows that will have frames 1-3 in one briefing window, and frames 4-6 in the other briefing window.
Type:  SYNC BRIEF.SYNC
9. Close the briefing windows by clicking on the upper-left corner menu bar, and selecting CLOSE from the window menu.

10. Exit McIDAS
Type:  EXIT