Starting to think guiding might be beyond me

[billyharris72]

Hi all:

I'm really struggling with guiding, which is proving to be a steeper learning curve that I had anticipated. Having eventually cracked how to calibrate PHD2 I have now run across abnother problem that I have not read about and am struggling to diagnose (though I have a suspicion). To start with, the kit I am using is as follows:

* HEQ5

* ZWO ASI1600MM  and Skywatcher 130 P-DS (imaging)

* ZWO ASI120 MM and QHY mini gudescope (guiding)

* Lenovo Yoga 3 laptop

* Hitec Astro EQMOD cable

* Software: AstroArt, Sharcap, PHD2

* A USB hub (a potential weak point, but I have used 3 different models now, including a StarTech, which seems to have a good reputation).

In my usual set up, a USB cable connects the laptop's USB (2) port to the (powered) USB hub, which has all the other kit plugged in. I find this helps keep the tangle of wiring under control. I use the USB 2 port because i) it is on the right side of the laptop and ii) I have had occasional issues with the camera disconnecting when connected to the UBS3 port.

Overall, for imaging without guiding my setup works okay. I do have an issue with controlling the mount through my gamepad hand controller - it works but has a tendency to just stop intermittently before restarting. Slewing and control direct from the PC EQMOD interface is fine.

I have tried guiding three different ways, and here's what has gone wrong so far:

1) Astroart for imaging and guiding. During calibration the machine occasionally locks up for a few seconds, with a message that AA is not responding if I click anything, otherwise with the spinning blue "ring" cursor. This never happens when I am not trying to guide. Calibration completes and I can image and guide, but the stars come out elongated (worse than with no guiding). This could be a calibration issue, but I've also noticed that every so often the cursor turns into that little blue revolving circle that basically means "wait, I'm busy". That's making me wonder if AA is locking up and becoming temporarily unresponsive during the guiding process as well.

2) PHD2 for guiding with AA or Sharpcap for imaging (originally AA, Sharpcap used to rule out a PHD2/AA compatibility issue). PHD2 connects to the equipment, calibrates and starts to guide. So far so good. Once the camera starts acquiring images guiding seems to stop, until a message pops up from PHD2 saying that it has not received an image for 18 seconds and has disconnected the guide camera. Error is consistent and reproducible.

3) PHD2 for guiding with AA or Sharpcap for imaging, but this time with the guidescope disconnected from the USB hub that everything runs through and plugged into the laptop's second USB socket. PHD2 connects to the equipment, calibrates and starts to guide. Once the camera starts PHD starts "pinging" to say it has lost the guide star, which from the display appears to have jumped from the centre to the far left of the screen. Error is consistent and reproducible.

I wanted to see if anyone has experienced anything similar. Could this be a software configuration or compatibility issue or is it something else? The issue with the game pad controller, quirky USB3 behavior and fact that happens with multiple software setups is making me think it might be an issue with the hardware, but want to see what others more experienced than myself think.

Thanks,

Billy.

 

 

 

[rl]

A lot of this sounds very familiar. I find one pc (I7, 16 gigabit ram) works ok for PHD2, qhy5 guide camera, APT, mount, and controlling a Canon SLR, all worked through a powered USB hub off a single USB3 connection to the laptop. If I change the SLR for a QHY183 then bad stuff happens much like you're seeing. I'm seriously contemplating a second laptop just to operate the main camera..I've never found a satisfactory answer. It all seems to be downloading the main camera..everything else will work quite happily together on a low spec machine. I'll be interested in the feedback. 

RL

[alacant]

Hi. Try the USB3 socket on your computer, but with the hub power disconnected. Works fine here with EQMOD-zwo120-dslr on the hub. HTH.

EDIT: zwo120mm: don't forget to update the firmware. 

[michael8554]

Hi Billy,

In example 3), you don't explain how the guide star has jumped across the screen.

Has the mount slewed?

Or has the selection box moved to another star?

If you autoselect a new guide star from the dropdown menu does guiding resume?

Michael

[Thalestris24]

Hi

Many such guiding troubles can be traced to usb limitations, especially linked to hubs connected to guide cams which much prefer having a dedicated usb connection. USB cables and connections can also be the source of problems. Once you sort out any usb deficits then guiding should, hopefully, be plain sailing - as long as the sky is clear.

Louise

[carastro]

I agree with Louise, I have tried several powered USB hubs and given up, they just cause disconnection problems, I have no problems without a hub.  I know they seem to work for some people, but it sounds to me like you're having the same bad luck as me with hubs.

I therefore gave up using EQMOd and just use the 3 USBs on the laptop for !. Camera, 2. Filterwheel and 3. Guiding.  If I want to use any more USBs I use a 2nd laptop.

Carole 

[Thalestris24]

25 minutes ago, carastro said:

I agree with Louise, I have tried several powered USB hubs and given up, they just cause disconnection problems, I have no problems without a hub.  I know they seem to work for some people, but it sounds to me like you're having the same bad luck as me with hubs.

I therefore gave up using EQMOd and just use the 3 USBs on the laptop for !. Camera, 2. Filterwheel and 3. Guiding.  If I want to use any more USBs I use a 2nd laptop.

Carole 

I think you should be ok sharing low bandwidth devices via a hub e.g. mount control is low bandwidth and so is efw and also an electronic focusser. But guide cameras and, increasingly these days, imaging cameras are high bandwidth, and I'd expect those to work more reliably with individual usb connections. But it's just my opinion and I could be wrong!

Louise

[Merlin66]

Billy, et al,

I use a 6 port powered USB hub mounted on the telescope pier to handle everything ( EQMod/ Focus motor/ Electronic finder camera/ imaging camera)

I have found keeping the guide camera/ PHD2 on a separate USB connection to the laptop to be more stable.

This is with a permanently mounted NEQ6pro, using CdC/EQMod/ AA6/ PHD2/ Artemis.

I never move the connections to the USB hub......

No issues, no drama.

(Edit: How is your hub powered?? I have a 12V to 6V converter rated for 5A feeding the usb hub, which is a usb2 hub.)

[carastro]

Forgot to say, I don't think it's guiding that's beyond your capabilities I think it's the hub factor.

Can you try guiding plugging it directly into the laptop just to eliminate that from the equation.  

Carole 

[kens]

yesterday I was messing aroung in daytime getting my OAG to focus. So I had the guide cam (Toupcam) connected through PHD2 and the ASI1600 connected through SharpCap. I've got a USB3 hub connected to a USB2 port on the computer so a similar setup. Basically I had the same problem which I have not had before using tools like SIPS to capture from the ASI1600. I think it could be a mix of bandwidth and Sharpcap running in video mode. Could also be due to the guide camera (a USB2 camera) as I normally use an ASI120MM-S but its width was giving me grief with the OAG. But I don't think I ever tried this config with teh ASI120 so I'll give it a crack.

One question for the OP: is your ASI120 MM the USB2 or USB3 version? The USB3 version is the ASI120MM-S . The USB2 model has reported issues when connected to USB3

[kens]

Just did a quick check. With the ASI120MM-S I didn't get any issues with it connected to PHD2 and the ASI1600 on Sharpcap but with the Toupcam (USB2) I got disconnections. The Toupcam was more stable when I ticked the LX mode option in Sharpcap. Sometimes with the Toupcam and ASI1600 I would also get issues with the ASI1600 images on Sharpcap with stripes appearing at very short exposures. Another sign of bandwidth issues. But at normal exposures (seconds not milliseconds) as long as LX is ticked things seem to work ok.

For imaging I use the SIPS software linked from the ZWO website. It has its quirks (like any other package) but is reasonably reliable and fairly easy to use. Its biggest quirks are:

• With ZWO cameras, every time you go to configure the camera it resets back to the default camera (in my case the ASI120 instead of the ASI1600)
• You need to tick the "Save images" box to save your files but it is on a different tab to where you start a sequence so its easy to forget and get a couple of hours of nothing saved even though they display nicely on the screen. 

Sharpcap seems better suited to video imaging. I only use it for manual focusing.

[billyharris72]

12 hours ago, michael8554 said:

Hi Billy,

In example 3), you don't explain how the guide star has jumped across the screen.

Has the mount slewed?

Or has the selection box moved to another star?

If you autoselect a new guide star from the dropdown menu does guiding resume?

Michael

A very good question and one I don't know the answer to. The jump appears to be immediate - the star jumps from one shot to the next - and I don't think the mount is slewing (that would be a big enough move to be audible). Equally odd is that, if I disconnect the guider (so no new commands) and then reconnect it, the guide star appears back in the centre where it started. It's really very odd and I have no idea what is causing it - I can only assume this is a software issue of some kind, but a not sure.

Billy.

[billyharris72]

Wanted to say thanks to all, as this has been really useful. It's reassuring to know that I'm not the only one with this problem, and that it seems to be readily solvable.

I've tried plugging direct to the laptop and that really doesn't improve things, so I suspect the issue might be the computer itself. It's one of these laptop/tablet hybrids that is aimed squarely at the leisure / consumer market and maybe the USB controller is just not up to the job. It also only has 2 USB ports so a hub is more or less mandatory if I also want to use EQMOD (I could potentialy drop this and see if it can handle the imaging cam plus guiding via ST4, though I like the fact that I can populate the FITS headers with info from the mount).

The idea of using 2 PCs (while far from elegant) might actually work. I've got an ancient laptop kicking around (if I can hunt down the charger) that I could potentially use for the guider (using ST4) while using the other machine for EQMOD and the imaging camera.

Oh, the joys of being out under the stars on a freezing cold evening, looking at my laptop screen and fighting with electronic hardware!

Billy.

[carastro]

Quote

Oh, the joys of being out under the stars on a freezing cold evening, looking at my laptop screen and fighting with electronic hardware! 

I know the feeling, and even when it all works fine, there sometimes comes along a day when for some unknown reason it goes wrong and you're sitting out in the cold trying to work out why.  

Carole 

[geordie85]

1 hour ago, billyharris72 said:

A very good question and one I don't know the answer to. The jump appears to be immediate - the star jumps from one shot to the next - and I don't think the mount is slewing (that would be a big enough move to be audible). Equally odd is that, if I disconnect the guider (so no new commands) and then reconnect it, the guide star appears back in the centre where it started. It's really very odd and I have no idea what is causing it - I can only assume this is a software issue of some kind, but a not sure.

Billy.

Could it be that your guide scope is not secure enough and is moving about?