Hi Brian,
Thanks for the post and firstly thanks to John for the follow-up.
John, it was great to meet you at Border Stargze!
As John points out, Argo Navis on its own does not directly drive stepper motors or
servo motors. It is a PUSHTO system rather than a GOTO. (However, see
further below).
Therefore, in the configuration you discuss above, you would retain your existing
tracking motors which would continue to perform tracking. In order to locate
objects during a manual slew, you would then install Losmandy part numbers
DSCH (Digital Setting Circle Hardware) and DGC (Delrin Gear Covers)
which we stock as our part number pn-g11-l-spec. These parts include a pair
of optical encoders, the hardware for mounting the encoders, a pair of
gear covers and an encoder cable. The optical encoders are positional devices
that then interface to the Argo Navis to allow it to keep track of the position of
the scope.
You can find a scanned copy of the installation instructions for the kit here -
http://www.wildcard-innovations.com....c_losmandy.gif
Many people prefer PUSHTO over GOTO because of its fast, quiet and reliable
operation.
Argo Navis also provides a modern and sophisticated user interface and
detailed databases and object descriptions including the type of coverage
the southern hemisphere warrants. Dialing up an object by name takes
seconds and there are sophisticated modes of operation such as identify
and tour modes as well as user loabable object catalogs which can help
bring rigour to an observing program.
As far as pointing performance goes, Argo Navis doesn't hide the facts and
tells you how it is. For example, it can assist you in measuring the raw,
whole-sky pointing performance of the mount and can analyse and
potentially compensate for many common systematic fabrication and
gravitational flexure errors within the mount/OTA. It can then also tell
you the "modeled" pointing performance of the scope and will provide
you with statistical metrics of the various mount errors as well as the
amount of polar misalignment so you can then judge whether they are
"real".
What's all this mean?
It can mean the difference between landing the object within the FOV of
your eyepiece of choice or blind pointing onto a CCD array.
This case study on a G-11 may be of interest to you -
http://www.wildcard-innovations.com.au/group_post_5573/
You will need a free Adobe SVG plugin to view the graphics.
Getting back to GOTO for just one moment. I mentioned Argo Navis does
not directly drive servo or stepper motors. However, it can be used in
conjunction with some third party motor controllers to provide full
GOTO operation. For example, use of the Argo Navis with a ServoCAT
servo controller is a popular choice on some Alt/Az and equatorial scopes.
I believe some users may have also retro-fitted third party servo systems
to the G-11 and are using it in conjunction with the Argo Navis.
Finally, Argo Navis is designed and manufactured in Australia and exported the
world over. It bears the C-Tick logo which makes it legally approved for
use in Australia. Always ask whether imported electronic goods carry the
C-Tick marking.
Thanks again for the post and for considering Argo Navis.
It was great to meet you at Border Stargaze.
Best Regards
Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place
Mount Kuring-Gai NSW 2080
Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au