The centering cross is practically invisible on eclipse maps except
in the dark total eclipse path. To show this, go to a known total
eclipse such as Babylon, April 15, 136 BC. (For observers, any
eclipse will do.) Set the field to 20 degrees, center on Al Hillah,
Iraq. If you didn't know where the cross is, you would never be able
to find it, you have to reload the map. There is a small open space
just below Al Hillah within the totality path, recenter on that. Now
re-center on a blank space in the first "partial eclipse" band, then
step outward band-by-band and see how the visibility of the cross
changes. The cross doesn't need to be colored. It might be more
useful in some cases if clicking on the toolbar gives a "black/white
option". One of these should always work.
I think this would be a useful feature, but I'm not a programmer. It
might not be worth the work.
Laren, using version 19 April, 2012
Laren Dart
http://ldart.got.net