Problems with CEM60 and SGP

Sequence Generator
21

I ran a daylight test this morning using POTH with the traffic monitor on. SGP was set to flip 1 deg past meridian.

As the mount crossed meridian), the driver started reporting the mount was now west of the pier when the flip had not yet happened. When it reached 1 deg past meridian, SGP initiated the flip and the mount slewed. SGP then aborted saying the mount failed to slew. Here is the output of the traffic monitor at the flip:

4:28:53
Altitude: 64:38:40
Azimuth: 182:43:17
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:38:40
Azimuth: 182:43:17
SideOfPier: West
Slewing: False
SideOfPier: West
SideOfPier: West
SideOfPier: West
AtPark: False
SideOfPier: West
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:38:40
Azimuth: 182:43:17
SideOfPier: West
SlewToCoordinates:
RA 11:48:59
Dec +14:28:53:
RightAscension: 12:17:44
Declination: +21:43:48
Altitude: 71:12:55
Azimuth: 162:33:36
SideOfPier: East
RightAscension: 13:41:10
Declination: +42:34:21
Altitude: 69:44:04
Azimuth: 73:26:06
SideOfPier: East
RightAscension: 14:50:41
Declination: +59:56:29
Altitude: 56:07:19
Azimuth: 38:45:05
SideOfPier: East
RightAscension: 16:00:13
Declination: +77:18:36
Altitude: 44:50:25
Azimuth: 15:48:05
SideOfPier: East
RightAscension: 09:06:07
Declination: +26:16:00
Altitude: 52:36:11
Azimuth: 261:50:57
SideOfPier: West
SideOfPier: West
AtPark: False
RightAscension: 10:15:38
Declination: +14:28:53
Altitude: 56:40:28
Azimuth: 227:31:36
SideOfPier: West
RightAscension: 11:25:10
Declination: +14:28:53
Altitude: 63:51:14
Azimuth: 196:23:28
SideOfPier: West
(slew complete)
Slewing: False
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:38:05
Azimuth: 183:16:42
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:38:02
Azimuth: 183:18:57
SideOfPier: West

SideOfPier: West
AtPark: False
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:37:54
Azimuth: 183:25:11
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:37:50
Azimuth: 183:28:00
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:37:47
Azimuth: 183:30:17
SideOfPier: West
RightAscension: 11:48:59
Declination: +14:28:53
Altitude: 64:37:44
Azimuth: 183:33:41
SideOfPier: West
SideOfPier: West

So to me it appears the driver is reporting which side of the meridian the scope is pointed, not which side of the pier the mount is mechanically sitting. Since it started west and ended west, SGP sees the flip has failed? Does this seem correct? Here is the corresponding SGP log showing the mount starting the flip west of pier:

[11/28/2014 7:32:01 AM] [DEBUG] [Sequence Thread] Checking if Meridian Flip is needed
[11/28/2014 7:32:01 AM] [DEBUG] [Sequence Thread] Telescope is on the West side of the mount
[11/28/2014 7:32:01 AM] [DEBUG] [Sequence Thread] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: 1.20231438774118 >= 1
[11/28/2014 7:32:01 AM] [DEBUG] [Sequence Thread] Running blocking meridian flipā€¦
[11/28/2014 7:32:02 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Starting Meridian Flip Procedure
[11/28/2014 7:32:02 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Skipping Solve and Sync
[11/28/2014 7:32:02 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Stopping the Auto Guider
[11/28/2014 7:32:02 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Sending Telescope command to execute meridian flip
[11/28/2014 7:32:02 AM] [DEBUG] [Telescope Thread] ASCOM Telescope: Pier side is West
[11/28/2014 7:32:02 AM] [DEBUG] [Telescope Thread] ASCOM Telescope: attempting pier flip using slew
[11/28/2014 7:32:02 AM] [DEBUG] [Telescope Thread] Telescope: Slewing to RA: 11.8164638888889 Dec: 14.4814
[11/28/2014 7:32:56 AM] [DEBUG] [Telescope Thread] Scope has completed slewing
[11/28/2014 7:32:56 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Telescope command to meridian flip has completed
[11/28/2014 7:32:56 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Telescope failed to perform meridian flip
[11/28/2014 7:33:26 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Procedure complete
[11/28/2014 7:33:30 AM] [DEBUG] [Sequence Thread] Blocking Pier Flip: Failed to meridian flip, aborting sequence (True)
[11/28/2014 7:33:30 AM] [DEBUG] [Sequence Thread] Run event requested sequence abortā€¦
[11/28/2014 7:33:30 AM] [DEBUG] [Sequence Thread] Checking RunEndOfSequenceEquipmentOptions, force = True
[11/28/2014 7:33:30 AM] [DEBUG] [Sequence Thread] In RunEndOfSequenceEquipmentOptions

Any ideas?
Chris

1 Like
22

Yes, thatā€™s correct. To be honest Iā€™m actually surprised that the flip happened in the first place! I guess you just got lucky.

iOptron will need to address this behavior in their driver. There is nothing we can do in SGP to fix this which wouldnā€™t be a complete guess. I would recommend you contact them about the incorrect SideOfPier behavior if you havenā€™t already. According to the ASCOM contract the mount should report the side of the pier that the scope is currently on regardless of where it is with regards to the meridian. The exception to this is when the scope is pointed below the pole but I donā€™t think this is the situation youā€™re running into.

Thanks,
Jared

23

Just FYI, Iā€™ve also emailed iOptron about this to see if we can get it resolved.

Thanks,
Jared

24

Thanks, At least weā€™ve shown where the problem lies.

I was testing with a target south, above equator so not below the pole.

Chris

25

I was just reading through the ASCOM standards documentation and am wondering if I am reading it correctly. It states that when the mount is east and looking west, with counterweight below scope, that is PierEast. So as a mount tracks across meridian it should move from PierWest to PierEast? Looking at my logs above, does it appear that the iOptron driver is reporting this backwards? It moved from a PierEast condition to PierWest as it crossed meridian.

I ran my sequence of the Rosette Nebula last night. It successfully stopped before meridian and the mount did the flip. When it restarted on the next target (still Rosette) it successfully plate solved and restarted guiding but it could never settle guiding. It became farther off, as though the guide corrections were reversed. Is this a symptom of wrong SideofPier? Or do I just need to check, ā€œreverse DEC output after meridian flipā€? I didnā€™t have to check that box with my Celestron AVX.

Thanks,
Chris

26

Chris,

If the ASCOM driver is not reporting Side of Pier correctly, then all bets are off for guiding behavior after the meridian flip. You could give that PHD2 setting that a try, it may fix it, or it may not. BTW, you can see PHD2ā€™s idea of which side of the pier you are on (as reported by the ASCOM driver) in the stats window View => Display Stats.

Andy

27

The simplest way tho think of this is that the mount should report the pier side from the side of the mount that the scope is on. If the scope is on the east side of the mount, thatā€™s considered PierEast. If itā€™s on the west side (looking east) thatā€™s considered PierWest. There is one exception to this and thatā€™s when the scope is pointed below the pole. In which case the pier side flipsā€¦but unless youā€™re imaging REALLY low (or youā€™re VERY north) this generally isnā€™t the behavior that people see.

I think youā€™re actually flipping because of a happy accident. However afterwards the verification is failing. Hereā€™s what it seems like is happening:

  • Your scope is pointed East (PierWest), however itā€™s reporting PierEast.
  • As your mount tracks through the meridian it (incorrectly) changes the pier side to PierWest
  • SGP sees that the side of pier is West and that youā€™re past your flip setting and SGP initiates the flip
  • The mount flips
  • Now the pier side is STILL staying West which is incorrect (It should be East).

This creates the following outcomes:

  • SGP and PHD both rely on your side of pierā€¦since itā€™s incorrect in SGP you say the flip failed. Since itā€™s incorrect in PHD they donā€™t flip the guiding and your guiding is hosed.
  • If you attempt to stop/start guiding you still see the same issue.
  • If you manually flip the calibration PHD will likely start to work.
  • Resuming the sequence will likely work but it will attempt to flip again as youā€™re mount is reporting the incorrect pier side (Coincidentally this explains the secondary flip attempt that flipped the mount back).

Hopefully the iOptron folks will be in contact shortly.

Thanks,
Jared

1 Like
29

I just heard back from iOptron. Theyā€™re addressing the issue and hope to have it fixed in a couple of days.

Chris (cmassaā€¦we have too many Chris here!) Iā€™ve volunteered you to test the new driver once the have it completed. Hope you donā€™t mind.

Thanks,
Jared

30

Iā€™d be happy to do that!!

Of course it will probably stay cloudy for weeks now!

Chris

31

Hi Jared

I just wanted to know if there has there been any progress from iOptron on this.

Regards

Alfredo

32

I have not heard anything back. Iā€™ll email them now.

Thanks,
Jared

33

I did hear back from them. It appears theyā€™re working on tracking it down. Chris R. is helping to better explain how it is supposed to function.

Thanks,
Jared

34

Thanks for the update, I was wondering too.

Chris M.

35

Looks like theyā€™re going to need to release a new firmware and ascom driver to address this. Iā€™ll keep you all posted with what I hear.

Thanks
Jared

36

Thanks again. Looking forward to it.

Big storms in California so no imaging for a bit anyway.

Chris

37

Jared

Iā€™d be interested if they can confirm if also new boards are required.

Regards

Alfredo

38

I exchanged several emails with the guy you passed on to me and he ended up saying he now understood.

Chris

39

I tried some imaging last night trying to resume the same target after letting the mount do the flip. I could not get it to restart correctly because the calibration would not flip in PHD2. I finally had to recalibrate and then restart the sequence.

Looks like until the pier side issue is fixed we are limited to automated imaging with the CEM60 on one side of the meridian only. Otherwise it has to be done manually. I guess Iā€™ll set up multiple targets on one side and go with that.

Chris

40

Ioptron said that this will be released by the end of the year. May want to check their site to see if itā€™s out there.

Jared

41

Thanks for the info. I checked the iOptron site this morning - nothing yet.

Chris