I have noticed something similar a few (maybe 3-4) times. I have
not been able to reproduce and I do not know what specifically
caused it. It may not be the same problem as yours, but I will
describe it here.
I use the G11 PMC-8 for astrophotography only and use NINA for
capture and control, with PHD2 for tracking, both via. POTH. When
I have seen it, it seems to track at something like twice the
normal speed. It keeps going and keeps going. The only way I can
stop it (and I only found this the last time) was to hit the
'stop' button on NINA scope control screen. This seems to make it
reset to normal sidereal tracking.
I had not determined whether or not it was a NINA error, PMC-8
error or something else - I just don't know. I've seen the same
thing enough times for it to be annoying, but have no further
details, nor logs. I was going to turn on ascom debugging/trace or
something so if it popped up again, I might have some useful logs.
Interestingly, I was going to run the Ascom conformance tool next
time to check general conformance, but this seemed to be very much
an edge case problem for me.
On 1/03/20 10:52 am, Jerry Hubbell -
Explore Scientific VP Engineering wrote:
On Sat, Feb 29, 2020 at 04:38 PM, Robert Spellman wrote:
After tracking well sometimes for over an hour the
mount suddenly moves off target ( not auto guiding just
viewing), I cad bring it back with the pad command sometimes it
resumes tracking sometimes it just keeps drifting
I assume you are using the Explore Stars application when this
occurs. The way Explore Stars works in POINT mode is that it is
continuously sending commands to move to the calculated position
based on the RADEC coordinates of the object adjusted for the
mount model set during the alignment routines. If the mount loses
communications with the tablet, it should track at the last set
rate which should be very close to the sidereal tracking rate.
When you manually position the mount using the direction buttons,
it goes into TRACK mode where the rate is fixed at the Sidereal
rate. I am at a loss to understand why the PMC-Eight would stop
tracking completely, perhaps it is not.
I assumed that when you said the mount moves off target that it
had stopped tracking completely. How fast does the mount move off
the target when this happens? Have you seen this behavior (loss
of tracking) when in TRACK mode?
The only other thing it could be, and this may be the case, is
that if the PMC-Eight loses communications completely with the
tablet, after 20 seconds the mount will stop moving. This behavior
is designed into the mount system. You can install a version of
the firmware that we have available on our website that disables
this function and allows the mount to keep tracking when not
connected to the tablet. When the tablet reconnects, it will
update the information on the tablet and continue to operate.
Vice President of
Explore Scientific, LLC.
jrh at explorescientific.com
1010 S. 48th Street
Springdale, AR 72762
Astrophotography: How Amateurs Can Generate and Use
Professional Imaging Data
Observatories for Amateur Astronomers: Using High-Powered
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Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
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+ Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100
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