Hi, I have an STX-16803 with an STX guider and an AO-X. The AO-X appears to be malfuctioning. So I have two questions: 1. Below is a link to a short video (sorry about it being on its side) showing what's happening--in pristine 1.0 arcsecond, windless skies, the guide star moves all over the place, and the "guiding" (such as it is) comes in fits and starts instead of being the constant 7Hz that it normally does. This is new behavior; normally, the guide star stays right in the middle, with very small guide errors. Does the AO-X have to be sent in for repair? http://www.de-regt.com/Problems/IMG_5084.MOV 2. Assuming that the AO-X has to be sent in, what settings do I change in Maxim to guide without the AO-X for the duration of the AO-X being away? Is it as simple as changing the camera to SBIG Universal?
I think it's very premature to assume it's an AO-X hardware problem without some diagnostics and analysis by our team. It could be a guide camera issue, a firmware issue, a software issue, a cabling problem, or even a computer issue. Correct. I'll ask @Adam Robichaud to help you with this... but I know the first thing he'll want to see is the logs.
Thanks, Doug! I have attached a couple of days Maxim logs, and some ACP logs from last night. The effect of this new behavior is twofold: (i) a lot of ACP plan get "failed," because the guide errors are too large to start imaging, and (ii) when not failed, the images have elongated stars.
Out of curiosity, did you try upgrading from 6.29 to 6.30? @Adam Robichaud rolled in some new fixes. Also, he'll want to know what changed from when it was working until when it failed.
I am on 6.29; last time I updated, lots of settings were lost, which was inconvenient. Should I update? I changed nothing; as we all know, there are gremlins in computers, but I did not change anything.
I have updated Maxim, and I didn't lose any settings. I have played around a lot with it tonight, trying to see what's happening. The following may be relevant: When I try to calibrate the AO, there is no motion (in both Maxim and in CCDOps. When I tell it to exercise the AO in CCDOps, nothing happens (but I do not get an error message; there is a bright guide star centered on the guide chip). When I image without the AO, the guide star is often streaked, and the errors are large (often well over a pixel, on a guide chip that is binned 3x3; ordinarily I would expect most errors to be well less than .5 pixel). Seeing is uncharacteristically poor tonight, over 2.4 arcseconds right now, so that may be a factor. (As seeing improved, so did the guide errors; though larger than I would like, they are now smaller than they had been.)
Remember how we did that exercise a long while back to test to see if it was moving in only one axis? Am wondering if the AO-X is not behaving in hardware.
I agree, which is why I did the things I did. This acts very similarly to that, except it's in both axes.
I'm going through the images taken last night (guiding without the AO). Some are streaked; some aren't. But I thought that perhaps this screen shot of a satellite trail, with streaked stars, might be useful. Also, the double-lobed aspect of the streaked stars is a common phenomenon in the images which are streaked.
Can you pop the instrument off the telescope, run the Exercise function, and check if the optic is moving correctly? https://cdn.diffractionlimited.com/help/maximdl/AO_7_Setup_Tab.htm
If you mean take the camera/guider/AO off the scope, so one can look at the AO glass to see if it's moving when being told to exercise (in Maxim, as described in your link?), I'll talk to the guys at SRO to do that with me. EDIT: We did as you asked, and they saw no sign of any movement in the glass, when testing at 200ms all the way to 500ms.
Is your filter wheel functioning ok? Reason I ask is to confirm I2C AUX port communication from camera is working; if the FW doesnt work either, then its cables or cameras. Does the red LED come on in the AO-X? Wondering if there is a hardware failure.
Colin, I've been imaging with the STX guider (not using the AO-X) for the last several nights, and most of the images are streaked. In particular, when focusing, the star used for focusing is streaked. I'm having the guys at SRO do some maintenance on my mount; I'll check back in tomorrow after they've done that, to report whether that made any difference. It seems to me that, if the tracking on the mount is jerky, that could cause havoc on the AO. Mark
Sorry for the delay; I'm dealing with COVID (not fun). My stars are still streaking, intermittently. I image two or three targets each night, but Tuesday night I only imaged one target (too much moon for the other target). All images were streaked until midnight, than all were fine after midnight (guiding with the STX guider, not the AO). I got to thinking that the mount may be doing something odd, so I'm in discussions with Bisque. Once we get that sorted out, we can get back to the AO issue (if one exists).
Yeah COVID is not fun. I hope everyone is okay. Does the tracking problem only appear when you're on one side of the meridian? If so then then backlash may be the issue, i.e. improper worm gear engagement in conjunction with whatever small OTA imbalance there is. Typically if there's any backlash at all, you need to have the mount lifting the weight as it tracks, rather than trying to pull it down. Otherwise the mount moves in fits and starts during tracking - the gear teeth disengage until it bumps into the next tooth, and then it flops over to the other side again. That's impossible to fix except mechanically.
Thanks, Doug. I seem to be improving, slowly. Yeah, I'm suspecting that it only happens on the east side of the meridian, but I don't know. Bisque is telling me how to take a log to show that.
Update: I worked with the guys at Software Bisque, without finding anything definitive. But, as time went on, the problem of double-lobed/elongated stars was affecting fewer images, to the point where, last night, it imaged all night without any apparent problem. So tonight, I told it to use the AO-X, and it's working fine. Yeah, it's a mystery to me (unless there was something caught in the worm gear, that has now worked its way out?). But I won't try to "fix" it anymore, unless the problem crops up again. Maybe it just needed a rest. Thanks for your help. Mark de Regt
