Ioptron IE Q 45 mount and PHD2 issues

[Lunam Seagull]

I wrote a while back to the fact that I was having problems guiding with my mount but then I had an Injury and was out of business for a while.
this was my issue

 I use a Ioptron IEQ 45 mount with an astrotech quadruplet using SSAG for guiding.
I upgraded my mount with a Pole Master for precise Polar alignment and updated PHD to the latest version PHD2

Since I did both things my guiding graph is worst than it was before.

 Apparently my issue was backslash and PEC error from when we talked about this

I corrected the backslash and use PEC correction.

According to Pole master I am dead centered on my polar alignment and I can do long exposures for as long as 10 minutes (so far)

my problem is my graph still all over the place and according to Guide assist my polar alignment is off by at least 9 arc sec

I reviewed the logs with Andy and he advice me as follows:

I looked at the last guide log (the largest one) and it looks like you guiding performance is limited by your RA tracking. There are large RA excursions at regular intervals. PHD2 is reacting to them and correcting them, but they are happening abruptly and there is only so much PHD2 can do to retroactively correct them.

(screen shot from PHD2 Log Viewer)

I think you will need to identify the source of these lurches in RA tracking.  You can run the PHD2 Guiding Assistant to get a better recording of the unguided RA tracking behavior.  You may need to get help from iOptron since abrupt 20-40 arc-second jumps in RA should not be happening.

Although unrelated to your guiding issues, I recommend that you install the ASCOM platform and use the iOption ASCOM driver to connect to the mount (and get rid of the ST4 guide cable.) More info.

I tried using the RS232 instead of the ST4 but I got the message that the mount does not accept pulse guide. Then I use both The ST4 guide with the mount also connected to the RS232
and seemed I got a better graph but still getting a RA error
It seems that I have some issue with the alignment of the polar scope and my telescope and that may account for the polar alignment error I get ( when I do two star polar alignment, then go back to zero position or any other area and slew back to the  stars used for alignment they are off) and if I slew to polaris it is off center as well)
these are the last two log files
I think I will need to send the mount to Ioptron to check what is wrong with the RA

Manny

[Andy Galasso]

Hi Manny,

Here's a plot of one of the Guiding Assistant runs, guiding disabled, RA in blue.  It would have been better to have let it run for at least one full worm cycle (400 seconds), but even with this partial segment of the worm cycle you can clearly see that the RA tracking has issues -- very large error (30+ arc-seconds), and at least one large spike (15+ arc-sec) that is too sharp to be guided out.

I think you're on the right track talking to iOptron -- the mount should be able to track better than that.

Andy