Measuring features with WINJUPOS
How to create a map of Mars so that you can keep track of how its features are changing
Despite its name, WinJUPOS supports all the main planets, the Sun and the Moon. It’s useful for preparing imaging sessions, providing simulated views of features at speci c dates and times. In addition, it has an excellent image measurement system that can be used to pre-prepare images for analysis or subsequent image processing routines such as de-rotation, which e ectively allows you to ‘undo’ a planet’s rotation to avoid motion blur. WinJUPOS can also be used to create maps of Mars during an apparition which you can compare with previous apparitions to see how its surface features are changing. Step 1 Open WinJUPOS and from the Program menu option click on Celestial Body and select Mars. From the Recording menu option select Image Measurement. In the window that appears, from the Imag. tab, click Open image (F7). Step 2 Enter image values under the Imag. tab as requested. Select the Adj. tab and ensure the Draw Outline Frame box is ticked. Press F11 (or Outline Frame Automatic detection) to align frame to image. Step 3 Adjust the outline frame to match Mars’s limb and orientation: arrow keys move the outline; N rotates clockwise; P rotates counterclockwise; PgUp enlarges; PgDn shrinks; space bar rotates by 180°. Use LD compensation to brighten the planet’s limb if required.
Step 4
Save as an .IMS (image settings) file via the Imag. tab’s Save button. Repeat for all capture images. It is recommended that once the outline frame has been set, leave it unadjusted for all similar images from the same session.
Step 5
To create a map from several .IMS files, select Analysis Map Computation… Click the Edit button and add the .IMS files to be used. Define where the output file should go in the Map file input box.
Step 6
Select the projection type required – the process is quick enough for experimentation – and press the Compile Map button (F12). WinJUPOS will automatically join .IMS files taken at different dates to provide a more complete picture.