CME F/E labels at moderate to high zoom levels when no coronagraphic data is present

[Jack Ireland]

This bug occurs when there are no coronagraphic images shown and only the disk of the Sun is shown.

CME F/E labels are positioned off limb at the position recorded in the HEK. When zoomed out from the Sun, you can see the F/E markers. If you zoom in far enough that the CME markers are no longer in the viewer window, then you come against the limitation that panning and scanning is limited to the extent of the image. When CME markers are shown when there is no coronagraphic data displayed, the CME markers are unreachable.

One solution is to generalize the notion of how big the vieweable extent in the viewer window should be. It should no longer be based in the image data, but rather which is the larger extent, either the viewable data or the most distant F/E marker from disk center.