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Alex

Back to Lake Michigan/Michigan City for the weekend.  Saturday had very
little air and even that was dying (big dome of high pressure moving
through) while Hammond was seeing 10-15 kt and 15-20 kt up north.  The high
clouds overhead came in every possible form and were spectacular, better
than text-book ideal. A great day to tie a line to a seat cushion, stream it
off the stern and float along behind the boat looking at the clouds. I wish
I had a camera with me.  On the downside, between glare off the 1-2 ft
swells and almost glass-like surface, and the following cloud cover, the
horizon was almost indistinguishable under the sun (approx 48d elevation).
The north and east horizon were very sharp, so I did a ton of IE checks
using the natural horizon and a smoke stack 5 nm away.  They did not agree
with sun IE checks, but more on that in another post.

I did 4 observations, although I did not expect much as it was almost
impossible to distinguish the horizon through a scope.  I was pleasantly
surprised with the average (using horizon instead of sun IC), although the
SD was well below my norm so that disappointed me. And my first set of
observations trending toward over shots ever!

     Error
#1   1.0'
#2   0.7'
#3   0.4'
#4  -1.2'
Hot, biting flies, and lower clouds starting to arrive blocking the sun 40%
of the time, so went swimming.

AVG  0.225'
SD   0.98'

I did go back to a set 2 weeks earlier, using the natural horizon IC instead
of the sun-derived IC, and AVG was reduced to -0.5' off, SD still 0.5'.

For the record, sun-derived IC (left eye, sextant vertical is 0.4' +/- 0.1',
horizon IC -0.1 +/- 0.1'

Needless to say, there are some target/shades/eyeball vs IE issues that have
me scratching my head

Bill



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