Clarifications for Jim.

[johnnysatstarhome]

Jim,
Thanks very much for your close and useful interpretations of my
photos from the test run. Unfortunately the fog came in so I didn't
get anything on Dec 8 UT.
Your surmise was correct as to Springville. Actually 7 miles north of
Springville at
-118.804855 (google) and N36.223841, in Tulare County.
Yes, I started the imaging at 4:54 local, or 0h 54m. The a in the file
name indicates it was the first image.
I would like a uniform scale and will work on how to do it. I use
Photoshop to crop the images out of the camera and so have to draw a
box each image, leading to some arbitrary scales. I'll try using the
rulers when drawing the boxes next time for more uniformity.
It was a good learning experience and enjoyable. Are we supposed to
send these images somewhere "official" or is this group's files the
repository?
John
at Starhome

[Jim Mosher]

> Are we supposed to send these images somewhere "official"
> or is this group's files the repository?

John,

To the best of my knowledge, at the moment this group's file area is
the only place where NASA is looking for amateur contributions to be
posted.

Someone has told me "unofficially" that as we speak NASA is busily at
work on a more "official" site with a larger storage capacity. But
I'm not sure if that will be for the preliminary training exercises or
just for the final impact next year.

In the meantime, it would seem nice if the organizers gave the members
of the present group permission to create "pages" giving a little
organization to the file area and the many questions that have been
asked. That's apparently a normal feature of most Google groups, but
for some reason it's not allowed here.

--

And thanks very much for the clarifications. I'll look a bit more
carefully at your north polar images (and Kurt's) now that I'm
confident I have the time right. Unfortunately I'm not completely
sure I know where the LCROSS impact targets at the north pole are.
The names assigned to them seem arbitrary and the coordinates may or
may not correspond to the maps I have. I assume the targets are
inside moderate-sized craters, but I'm not sure which ones. I guess I
need to look into that a little more carefully.

As to image scale, I should think you would get pretty consistent
results if you use the same setup from night to night and are careful
to resize the cropped sections by the same PERCENT in Photoshop. For
a given setup, the raw arc-second per pixel scale of your images
should never change much, and kilometer/arc-sec scale on the Moon will
also change only very slightly on successive nights. So your results
should be pretty uniform if you settle on a fixed PERCENT of the raw
image scale. You can then crop out whatever subsection you want,
either at the beginning or the end, without changing the scale.

On the other hand, depending on your mount, the Moon's rotation angle
(and that of any other object you photograph) can change drastically,
even in an hour or so. So some rotation may be needed to make the
images match.

-- Jim

On Dec 8, 9:00 am, johnnysatstarhome