[Kstars-devel] Atmospheric Refraction trouble

[Akarsh Simha]

Hi Alexey and others,

I don't understand how the current unrefract() in head actually
converges.

Of course, it shouldn't work under the altCrit, because the same
function is not being used, but even otherwise.

If I understand right, we just keep subtracting the refraction
correction from the initial altitude. However, note that as the
altitude becomes smaller, the correction in fact, keeps increasing. So
we are going to go and plummet into 0 altitude.

Maybe it works only because of the existence of the below-altCrit
bug. The bug makes sure we use a function with the opposite slope
later, so maybe it comes back and converges after many more cycles
than it should actually take.

I'm guessing so because it does not work with my changes that hope to
fix the below-altCrit trouble.

While I try testing this hypothesis, I'd be helped if Alexey could
explain his logic behind the unrefract() code.

Thanks.

Regards
Akarsh