Re: Scope xtrol/mag limit/RealSky on hard drive

Robert Burns Nov 19, 2002

Bill,
If theOuranos box is still available, it's cheap, so I may buy one.
If I do, do you have any idea what sort of pointing accuracy I can
expect using Guide7, M.E.C. and the stock encoders on a Losmandy.
(Taking in to consideration quadrature/gear ratio, the resolution
works out to 4096 steps on both RA and DEC.

Also, because I gearing up to hunt asteroids, I need to compare the
fields of my CCD camera and Guide7. A one-minute integration with
Starlight Xpress MX716 seems to be showing me star mags of 16 or so.
It would be great if I could make Guide7 show comparagle star
magnitudes so I could compare what I'm seeing from the camera to what
Guide7 is showing me. I really don't want to haul USNO A2 outside.
The two cds of the GSC-ACT catalog might me more doable, but what
sort sort of mag limit would it give me?

Thanks,

RB
--- In guide-user@y..., Bill J Gray <pluto@p...> wrote:
> Hi folks,
>
> Robert Burns asked about an automated "slew scope", in which
Guide
> would simply read the Sky Commander's position every few seconds and
> update accordingly.
>
> Right now, no, it doesn't do that. Only the Tangent
Instrument
> boxes are rigged for this (you push the scope around, and a little
> indicator follows it on-screen, and the chart recenters after you
> push the scope far enough.) One more side benefit I hope to reap
> from the rewriting of scope control in Guide... in theory, if
system
> A supports thus-and-such Guide-related feature, system B will
support
> it, too. (At present, each system is treated independently. That
> led to a maze of redundant code... it's quite ugly!)
>
> Robert also asked about the limiting magnitude shown by Guide,
> "out of the box". That would be the same as the limiting magnitude
> of the GSC, which varies according to where you are in the sky.
> In sparse areas, it goes as low as mag 15 or so. In dense areas,
> you're lucky to get much past 13.5. (The folks who put GSC together
> went for a certain number of stars per square degree, _not_ for
> a fixed limiting magnitude.)
>
> For a given area, you can click on some of the fainter stars
> shown and read their magnitudes... keeping in mind that GSC
magnitudes
> are notoriously unreliable. (Brian Skiff once made a remark along
> the lines of "don't trust GSC magnitudes for anything. No, not
> anything.")
>
> Alan Cahill asked about use of RealSky from the hard drive.
Only
> way to do this is to make a subdirectory, say, c:\realsky, and
> copy the RealSky CD(s) into it, maintaining the subdirectory
structure.
> Then you need to create a drive letter pointing to that directory.
> In DOS, the SUBST command can do this, for example:
>
> subst h: c:\realsky
>
> You can then use the "Extras... DSS/RealSky... RealSky/DSS from
CD"
> option, and change the drive letter given in that dialog box to
> that of the newly-created "drive", and extract the image just as
> if it came from a CD-ROM.
>
> -- Bill