ZWO ASI ASCOM camera selection


I realize this may be a ZWO ASCOM driver, or ASCOM issues vs. SGP, but I’m having the following issue both in SGP and PHD2.

I have three ZWO ASI cameras, two in use at any one time, ASI174mm-cool, ASI1600mm-cool, ASI1600mc-cool.

One used for imaging in SGP and one used for guiding in PHD2.

Works fine but if something goes wrong and equipment needs to reconnect both SGP and PHD2 can end up with the wrong camera, either guiding and imaging reversed or both programs trying to use the same camera.

Also when starting up I need to verify that the correct camera is selected in each program.

While I’m at it. ASI cameras (at least the asi1600) seem to always default to 8bit, when I want 16bit.



in another forum, a user said he uses the native ZWO dirver, with SGP, and it pops up a dialog to select which camera when multiple cameras are connected.

I don’t see that when I try it. current zwo dirver.

Any ideas?


If you have 2 ZWO cameras connected SGP should prompt you as to which one to connect (at least once). SGP also saves the ZWO camera that you last connected to (as it’s likely an imaging camera and probably not your guider). If you want to reset this saved camera you can do so from the ZWO settings menu:




OK that works.

So we have “default” gain and offset there, and per event gain and offset (optional) in the event settings.

I guess the only functionality left in the ASCOM driver is USB throttling (which I haven’t needed). Do we know what the USB throttling is/isn’t in the native driver?



I don’t believe we have access to it in the native driver. I’ll double check. If we do I won’t expose it as this is the #1 way to get the ZWO camera into a bad spot. We’d just pick something sane and leave it there. Also in my testing the USB Limit with the ASCOM driver makes very little difference for stills, maybe video is different?



OK no worries on the USB.

It seems like it is asking me to pick a camera every time I connect.