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Hi Brad,

This new version is another big leap forward. Congratulations on this.

You mentioned the difficulty of keeping everything lined up at once. I
think the nature of the development of this project is iterative,
fixing one or two issues at a time until all are gone. You are
producing the iterations pretty quickly so the bugs are nearly all
ironed out. You will be at the "bells and whistles" stage  by next
iteration.

Here are my comments on your latest version (ver 8):

1)The only problem I see is that the LHA (blue template)and VE (both
Star Base and Ecliptic)alignment are much improved from last version
but the blue template and the Ecliptic still seem to be off by one
degree relative to the Star Base. First, to align the LHA (blue
template orientation) with the Star Base, try this: With Star Rotation
at zero (so that the VE of the Star Base is at 0 degrees or 12:00
position - or at least this is my understanding). Now adjust the LHA
so that the 180 deg. index line extension on the blue template is
exactly dead straight up. Notice that LHA is -1. LHA should be zero in
this case. So it appears that there is an "off-by-one" error
somewhere. To
give another example, Archernar should be at 24 deg SHA (LHA) but is
currently showing 23 deg. If you fix this then the blue template, LHA
display and the Star Base will be in synch. Now, turning to the
ecliptic, with Day Of Year at 79, and with the 180 deg. line at
exactly at the dead straight up 12:00 position, the 180 deg line
should exactly bisect the solar disk, but it currently appears to be 1
deg off. If you rotate the ecliptic 1 degree to obtain a bisected disk
then this will be aligned also (Oddly, it seems to perfectly  bisect
in the S. Hemi as it is...)

2)The extension of the 180 deg index line is very helpful - too bad an
arrowhead wasn't possible, but not a big deal. (Oops, my N. Hemisphere
bias is showing. This line is also the 0 degree (due North) line when
in the S. Hemisphere).

3)When you rotate the stars beneath the Blue Template, the LHA changes
accordingly, but the LHA slider doesn't move. When you subsequently
move the slider, you see that the slider range is no longer 0-360 (for
example, if the Star Base is rotated 90 deg, then the LHA slider range
becomes 90->0->89. I suspect you may be running into a limitation of
Excel (it might be time to consider porting this application to Java).
This is a "can live with it" issue.

4) I see you brought back the feature of the latitude change (Zenith
"+" mark)going beyond the equator (so that if the N. Hemi Star Base is
selected, 10 deg. S Lat is displayed by the blue template graphic as
-10 deg N.; and if you take the Lat to 90 S. you will get the
"donut"). This is an interesting display and a perspective you cannot
get in a real 2102-D, but some users may be surprised by it; Latitude
range of 90-0 (as you had in REV. 4) might be preferred by some users.
I also noticed that if you have the Star Base in N Hemi mode and move
the Latitude into the S Hemi, then change the Star Base to S Hemi (in
an attempt to make the two agree), the Blue Template will change to N
Hemi (so they still will not agree). This is not wrong, just maybe not
aligned well with user's expectations. I suggest that if you leave it
like this, that you move the Star Base radio buttons to the top (above
the sliders) to indicate that the correct Star Base must be selected
as the first step. This is of course the same as with the real 2102-D.

5) Yea! Correct the spelling of Alphard! (Note: In Japan, Toyota Motor
Co. currently sells a large family-type minivan named "Alphard". Of
all the star names available, this is probably the last one I would
have picked! Although "Zuben Elgenubi" might be worse). Here is a
link- http://toyota.jp/alphard/

6) I would like to see Polaris added to the Star Base (On a real 2102-
D, this isn't possible because of the center pin). Some might argue
against this since Polaris is "not one of the 57 Navigation
Stars" (which never ceases to surprise people). But we all know that
Polaris is a very special star, and even has it's own special pages in
the Nautical Almanac, so I think it deserves a place (a position line
from Polaris is just as valid as any other position line for a fix,
and in addition gives you your latitude, or very nearly so). I think
you should add it. This will be yet another improvement of the 2102-E
over the 2102-D (in addition to the sun display)! Or, failing this,
you could plot a dot in the center to represent the center pin/
celestial pole. For the South Star Base, the center dot might make
more sense since there is no star at the pole. Somehow it is
comforting (to me at least) to see that the stars are rotating around
something. Users in the S. Hemi might accuse me of a "N. Hemisphere
bias" in feeling the need for a visible reference point such as
Polaris for the celestial pole and perhaps that is true; maybe they do
not feel the need for such security blankets.

7)Can you add an outer circle to the Star Base indicating the limit of
declination? (i.e.,the South celestial pole in the N Hemi Star Base,
and North celestial pole for the S. Hemi Star Base).

Any other suggestions for Brad out there?

Regards,
John
Tokyo, Japan
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