ZWO ASI 120mc PHD2 issues/solution(?)

[Alexp]

Hi everyone,

long time lurker here, but now I thought I'd mention something here. I have not had the time to use my telescope setup in years but I am finally taking the time to catch up again on everything. Currently I am using a Celestron AVX with a SW 150/750pds and a 9x50mm finderscope with the old (untrusted it seems) ASI 120mc as guide cam. I am connecting my entire setup to a Lenovo Legion laptop with Windows 10.

I am writing this here since I have encountered an issue with PHD2 and my ASI120mc and I have found some odd solution from other threads to another product here and over at cloudynights. I am quite new to all these problems and problem solving so please excuse me using a lot of laments terms as my knowledge is very limited here. 

Anyway, my guide cam always keeps losing connection when trying to use it in sessions and I kept receiving a message from PHD2 something like "An image has not been acquired after XX seconds so the camera has been disconnected". Sometimes it was working for a little while, but PHD2 kept "lagging" resulting in very poor guiding, but ultimately the connection to the guide cam was always lost. 

I have found a few topics on this in forums, most often suggesting turning off automatic USB power management to the USB ports (did that), disabling C states in BIOS (not an option in my BIOS), updating firmwares and softwares of all the relevant programs and cameras (did that), getting a powered USB hub (have that), switching to 8bit mode in PHD2 (did that), using USB 2.0 instead of 3.0 (did that), etc. etc., or simply giving up and getting a new guiding camera. Except for the last "solution" I have tried out everything I could but nothing has worked.

At the same time, my QHY polemaster also kept dropping frames. When I searched for this issue I found a few topics where others have mentioned that the problem here has to do with the USB power management/savings from Windows. In these topics others have mentioned that a weird way to resolve this issue is to have a video, or a Youtube video run in the background on your laptop while using the polemaster software as this somehow stops the USB power management from changing the power supply to the USB ports. 

I have tried this and suddenly the polemaster software started working flawlessly again. As it seems that QHY and ASI both are using similar hardware components in some if not many of their cameras, but moreso as this seems to be an issue with the USB power management I thought I may as well give PHD2 with my ASI120mc another go while having a video run in the background. And suddenly PHD2 is also working flawlessly without losing connection to the guide cam! 

This is not a perfect solution but it does work. I have searched a long time for solutions to both the PHD2/ASI120mc and the QHY polemaster software problems but whereas I have found this video solution to the QHY polemaster, I have not really found this odd approach as a suggestion to the PHD2/ASI120mc problem. So I thought I'd post it here just in case there is anyone else that encounters the same problem and did not find a solution other than maybe buying a new guide camera. Has anyone else encountered this issue with the ASI120mc and resolved the problem in this same way?

Cheers

[Adreneline]

Interesting.

I noticed when using PHD2 to create a dark library and BPM with my ASI120MM-mini and my ASI290MM-mini that PHD2 kept losing connection with the camera(s), more so with the longer (>3 s) exposure times.

I rarely use a PC with my setup but when I do I have experienced loss of connection problems with the guide camera.

[Alexp]

I had the same issue while creating a dark library and bpm.

When there was a video running in the background while using PHD2 and after I was done with my session I turned the video off and on a few times to see if this has an influence on PHD2. And surprisingly it did. Everytime I turned off the video lagging started up until the point where the camera got disconnected. When I turned the video back on PHD2 ran smoothly again.

If you ever tried this out, I'd be curious to hear if this quick notfix with running a video in the background would help you as well but if you rarely use a pc then I guess it won't be that important :).

[Adreneline]

3 minutes ago, Alexp said:

If you ever tried this out, I'd be curious to hear if this quick notfix with running a video in the background would help you as well but if you rarely use a pc then I guess it won't be that important :).

Hi.

Very interesting! I mainly image with ZWO cameras and an ASIair but I want to do some imaging with my 6" RC and a Canon M6 MkII using BackYardEoS - I need to get guiding working with my CEM25-EC mount but to date I have been beset by problems. I will definitely give it a go at the first opportunity and let you know.

Adrian

[Alexp]

Hi there,

I hope that this odd thing will help you and if so, I hope that more people will find this as it took me quite a while to figure this out, but maybe I am just a slow learner ;). 

Good luck on this and do let me know!

Cheers