PHD2 losing Connection with 120mm

steve789

I recently purchased a second hand ASI 120mm to use as a guide camera. Its the older 120mm without the ST4 port and I'm using it with EQMOD through a HitechAstro EQDIR cable. Its a great camera and I would be really pleased with it but for an intermittent issue when using it with PHD2.

During a couple of imaging sessions I've set up guiding and left PHD to do its thing only to return to my laptop later to find PHD has stopped guiding and is displaying a message saying it has lost connection to the camera. I've had several sessions where the camera has worked flawlessly but a couple of nights have been lost due to the disconnection problem repeating throughout the night.

As well as PHD I also have EQMOD, Stellarium Scope and APT running. I have 4 USB ports in use during imaging. 1 for the ASI 120mm, 1 connecting a Canon 450D to APT, 1 for the EQDIR cable to my HEQ5 mount and 4th one is used for an XBOX wireless controller.

Any suggestions to what might be causing the issue? Could it be a USB conflict or could it be a dodgy cable? I have tried wiggling the cable but haven't lost connection that way.

Any suggestions would be greatly appreciated. I can't afford to lose any more sessions this way, clear skies are too rare!

Sam@ZWO

do you use any hub?

I would suggest you connect the camera directly to your laptop without hub

we got some feedbacks that EQMOD cable will lost connection when use ASI120 camera

so are you use it was ASI120 lost connection?

steve789

Hi Sam, thanks for the reply. All my devices connect directly to the laptop.

Its definitely the camera losing connection. The message PHD2 gives me is something like "Camera timeout. PHD has lost connection to the camera. Please resolve..." So I click on the camera icon to bring up the connect equipment window, reconnect the camera and the cycle starts over.

I had a 6 hour session last night and the problem persisted. I tried lowering and raising the USB Traffic slider, swapping usb ports around and changing the cable all to no avail. Eventually I got stable guiding by changing the driver in the Connect Equipment window from "ASI Cameras ASCOM driver" to "ZWO ASI Cameras" which I assume is the one built into PHD. The picture quality wasn't as good with this driver but that my be down to a poor dark library (I've found it sometimes takes a couple of goes to get a successful dark library in PHD2).

With the ZWO ASI Cameras driver I was getting a maximum of 15 minutes before the dreaded Camera Timeout message. After changing drivers I got a good 4 hours of faultless guiding.

Sam@ZWO

then its hard to say what cause this problem

I tested it for one night before and it works well

can you send me a email? sam.wen(at)zwoptical.com

I think we need more info to try to fix this problem

mrray

In PHD2 on the Camera Tab in the brain there is a Disconnect timer box. Try raising it a bit.