I'm going to have to try this. I'm not sure about the sequence of those steps you check off, Track-Focus-Align-Guide. I've been focusing before I run the sequence at all, now I'm wondering if it really does the steps in that order. if so, I'll need to have two dummy steps, One to move to the bright star and align, then a second step to do a no-op move to the same place and focus.


For some targets, it really isn't possible to autofocus without slewing the mount. It would be nice if there was an option for that module to tell Ekos/Kstars to slew to some "nearby" star above a certain magnitude. In the meantime, I supposed I can do this manually as an step in the sequence, i.e., add a target I don't really care about, have it autofocus, take a short (throw-away) image, then go back to my real target.


Well, that turned out okay after all. I dropped the hub and connected directly to the mount and ASI1600 using that latter as the hub for the filter wheel and guider. I did continue to get USB resets, as you said, on every exposure, but nothing every locked up or failed and I wasn't forced to power cycle or physically reconnect anything.
so I guess I'll need a new hub it I want to move further away from my mount.

I have to say that this still feels. wrong. It sounds like either there's an issue with the ZWO driver or the API isn't being used correctly because I can't see how normal, correct use should result in a device reset on every exposure :-/



Well, that's not a happy thing to hear :-( Because the only other references to this slew of failures I can find suggest an issue with the USB controller on the motherboard of my laptop. 

I think I can try without a hub by using the ASI2600mm as a hub for the filter and guider then a different cable direct to my laptop for the scope. I'll give that a try this evening. 



Last night I set up with my AT6RC and ASI1600mm for the first time in a long time. I have an ASI174mm mini for a guide imager. Things seemed okay at first, and polar alignment went smoothly.

I'm running on an old laptop (Thinkpad T420s) running Ubuntu 20.04.

Then, I started getting various USB errors. I would lose my connection to the scope. I would lose my connection to the main camera. I would have to unplug everything and restart. Eventually I tailed syslog and saw a constant stream of usb reset  messages. Once those started, everything would go downhill rapidly.

roland@astro-02:~$ lsusb
Bus 002 Device 004: ID 17ef:1003 Lenovo Integrated Smart Card Reader
Bus 002 Device 003: ID 8086:0187 Intel Corp. 
Bus 002 Device 046: ID 0403:6015 Future Technology Devices International, Ltd Bridge(I2C/SPI/UART/FIFO)
Bus 002 Device 042: ID 2109:2817 VIA Labs, Inc. 
Bus 002 Device 045: ID 03c3:1749  
Bus 002 Device 044: ID 03c3:1f01  
Bus 002 Device 043: ID 03c3:1604  
Bus 002 Device 041: ID 04b4:6572 Cypress Semiconductor Corp. Unprogrammed CY7C65642 hub
Bus 002 Device 040: ID 2109:2817 VIA Labs, Inc. 
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 0a5c:217f Broadcom Corp. BCM2045B (BDC-2.1)
Bus 001 Device 003: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

device 45 is unnamed, so I had to dig a bit
Bus 002 Device 045: ID 03c3:1749  
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x03c3 
  idProduct          0x1749 
  bcdDevice            0.00
  iManufacturer           1 ZWO
  iProduct                2 ASI174MM Mini
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:

Unfortunately, I didn't check the other times to verify it was only and always this device. I'll try some daytime connectivity testing to see if I can figure this out, or maybe try again tonight and leave that 174mm unplugged to see if it's only that. The 174m was plugged in at times to a USB hub, and at other times (when I captured the above) to my ASI1600mm. 

The only thing close to this I've found was here: github.com/indilib/indi/issues/950 and that was two years ago and doesn't have a clear resolution (nor is it clear to me it's the same thing except for the general USB reset symptom).

Any suggestions besides trying again? I do have second laptop with the same set of software I can try, and I can swap out cables. I had already tried various USB ports on the laptop and swapped out the main USB cable but that was before I found the link to the 174mm; I'll try to reproduce this and then swap out those cables.


And the 3A is enough? I saw those and wasn't sure. I actually had some problems with the power supply that came with the SM but maybe it's not actually working correctly.


I see from this post that the StellarMate package now includes a cable for this, but I have an older one that didn't include that cable. Anyone know of a 3rd party cable for this? I've tried supplying directly from a USB 3 hub that is supplied by 12V, but that won't do it.


Some mounts have a setting to do this, but many (most?) do not. And I'd guess this ends up be a per-driver thing, though in principle it doesn't have to be. As a former ACP user, I know they can do it for mounts that have no built-in support for consistent approach slewing. 

So the question is, is this already hiding someplace in INDI/Ekos, or would it be a new feature that has to be added?

One thing that has lead to me to wanting this is that I'm trying to figure out a way to do dithering via pointing for when backlash is an issue; and yes, I've got too much backlash to do dithering well via guiding, especially in Dec. And my Canon T6i cameras show some horizontal banding that I suppose I could work around by rotating the cameras, but I kind of like the camera axes to line up with RA and Dec....

If I treat the problem as it I were building a mosaic that overlaps about 95% and had consistent approach slewing with some sloppy tolerances, I think I can end up with an effective workaround. But consistent approach slewing would be good in general since it would mean there should be little backlash to deal with at the end of pointing.


Last night PhD was guiding perfection. Today it kept losing the connection with the camera. Somehow, I had managed to make exactly this mistake and apparently reset something so it was trying to use the native driver instead of the INDI connection. I had turned off autoguiding to get imaging done while I came inside to try to find out what was going on. This post and thread saved me a lot of grief. I went back outside, found that was exactly the problem and voile, guiding worked again.

Of course, that's when the clouds rolled in.


Roland Roberts replied to the topic 'Ekos polar align help please' in the forum. 2 years ago

hades wrote: For me it seems that you are too away from NCP, that's why the vector is out of the screen.

I'm late to the party on this one, but yes, I agree. I have an AstroTech AT6RC mounted on a Celestron CGX-L and have this problem routinel if I try to use the main scope for polar alignment; the FOV is just too narrow. The CGX-L doesn't have an integrated polar scope.

But... unless the focal length of your guidescope is rather long or your guide camera is really tiny, you should be able to get close enough to keep the NCP on screen. If not, follow the instructions the others gave you; pick a star and move it closer, then repeat. I often do this repeat even if I didn't have to move offscreen, just as a check of whether or not I did a good job vs maybe having bumped the scope while aligning....