Re: [guide-user] Charon not opening, and is obsolete (or not)

Bill J Gray Jun 18, 2012

Hi Matt, Clay,

> "...Charon (recently installed) won't open.I remember this one but its been a few
>years......There was some fix (deleting some file. May have been a tdf) anyone
>remember?"

Um. I don't recall this, but you might delete 'charon.pif'. This is a "program
information file", and I could imagine that it might cause grief.

If that fails, I'd need more info: what happens when you attempt to run Charon?
Are you running it from within a DOS box? Do you get any error message(s)?

It would also be possible to run into trouble with the initial setup. At first,
horrible as the idea may sound, set the program to run in 640x480, 16-color mode.
That will at least work (and will look better than it may sound). Once you get
an image on-screen, you can experiment with the other modes and see which work
(there are about six available resolutions, as I recall).

> ...I noticed that Bill describes Charon as 'nearly obsolete'.

True. I stopped most work on it largely because I was very impressed with
the work by Bob Denny (PinPoint), Herbert Raab (Astrometrica), and Brian Warner
(Canopus). To keep up with the pack, I'd have had to move to something
truly Windows-based, after which I figured I'd just be duplicating what these
three gentlemen had done anyway. Not to mention that each had pushed things in
some directions I'd not managed: fully automated plate solving, track-and-stack,
and photometry, respectively.

Adding to this, the source code has become somewhat horrible. That source
code is posted on my Web site. I should probably remove it; any potential
employer who saw it would immediately decide that its author should never be
allowed near a computer again. The problem is that it started out with one set
of goals, and then more goals were added, and more features, and... sort of
as if one built a bicycle, and then decided it should be able to go on water
as well, and then added the ability to fly. If I did further work on astrometry
or photometry software, I could almost certainly use some components from Charon,
but it would be well to start out mostly from scratch.

Every now and then, something has come up that has almost tempted me to get
cracking on the program again. In particular, a while back, I read a paper
about astrometry.net. This project does something I thought about doing about
two decades ago, but didn't think would probably work: it can take any image
and pattern-match and plate solve it, without needing to know where it is in
the sky or even what the image scale is. (Charon, as you know, needs at least
an approximate image scale and you have to give it an approximate plate center,
and it runs somewhat faster if you can give it an approximate rotation angle.)

This could lead to a super-duper "digital finder": point your scope anywhere
in the sky, maybe not even bothering to align the scope; take an image; and
Charon would figure out where in the sky you were. Which would be pretty amazing!
But that's what astrometry.net does. Unfortunately, it requires broadband
access; you upload your images and get the pattern match results returned to you.

-- Bill