Hi Ron,

If you have reliable network like mine (Gigabit LAN) then I'd recommend the following configuration:

1. RPI3 + Powered USB Hub for INDI Server
2. KStars/Ekos as client on a more powerful machine.

Now KStars for Windows is still work in progress so it might not be at stable as its Linux counterpart but it's getting there. For remote operations, there are practically no difference between KStars on Linux and on Windows. You can follow Ekos on Raspberry PI tutorial but simply skip installing Ekos on Raspberry PI as it is not required nor you need VNC since you'll be remotely controlling it via Ekos.

Thanks, that sounds good. I have a dual Pentium 3.2 Ghz 4 Gb machine that I use for image processing. Kstars seems to run just fine on it under Windows 7 64 bit version. So I think I am good there. I have a spare Rpi3 laying around I may just pick up a 32 Gbit SD card and load a whole new system on it just for this project, then all I need is the hub.

thanks again.
Ron

I asked, on the SBIG forum, if they had an ASCOM driver for their cameras and their response was that they do not currently have one, but that should change later this year. My plan is still to implement the Rpi as the INDI server anyway so I will not have to wait for them to develop their driver.

thanks,
Ron

Knro,
I read this on the INDI LIbrary site;

You should power up your Raspberry Pi from the same USB hub you are connecting your CCD to. Powering Raspberry Pi with its own power supply will result in your CCD and Raspberry Pi do not have common ground (GND). This leads to non-zero voltage potential on all wires between your CCD and Raspberry Pi, including data lines. The noise identified on the images represents the current related to this non-zero voltage potential.

Is this something you do? My SBIG CCD has its own power supply, so that will make it impossible to power both the CCD and Rpi from the USB port. I have not tried this yet so I don't know if I will experience more noise or not. From what I understand you cannot backpower the Rpi3 thru the USB anyway (at least not at boot up). I have also read that the Rpi is only grounded thru the monitor cable, so in headless operation is it just floating.

I guess I will have to wait until I get to try this out to see if there is a problem or not, unless anyone here has any input to add.

thanks,
Ron

It seems this was related to ATIK perhaps? I don't recall. My QSI has its own power supply for over 3 years and it's working fine.

ok, thanks
One other question. I want the Rpi INDI server to access the CGEM mount. I purchased a Rpi GPIO Tx/Rx to DB9M RS232 Serial Board to plug into the Rpi. Not sure why I did not buy just a USB to serial adapter instead, but this is what I bought. It is supposed to level shift from RS232 voltages to TTL voltages for the Rpi. Does anyone have experience with this approach, I don't want to fry the pi!

thanks,
Ron

I have authored this. This is related to so called ground loop for cameras powered from RPi over usb. It may result in a pattern on images taken by such cameras (in my case it was Atik Titan). I don't think it applies to cameras with their own power supply. In such cases data lines are well separated from power lines.

How does one typically connect their RPi to the network? Via cable to a Gigbite LAN, or wireless 802.11ac?

Out-of-the-box the Pi 3 Model B supports 802.11n having a speed of approximately 150 Mbps, and a 10/100 ethernet port. Neither can keep up with the USB 2,0 speed of 480 Mbps that interfaces to your camera. The ASI120 can deliver a resolution of 1280x960 pixels at 35 fps. That is 344 Mbps at 8 bits per pixel or 430 Mbps at 10 bits per pixel. Those rates push the limits of the USB 2.0 interface.

So this begs the question: If you have a relatively slow network connection, and you choose to stream video for 10 seconds. will the INDI driver use the PI's free RAM to buffer the video? Is the size of that ring buffer configurable?

Thank you.

I use an ethernet cable from the Rpi to my router and that is also hard wired to the remote pc running the software. I have not tried video, I just have to wait for the full frame image to download from my SBIG camera. It does not seem much longer than if I had the pc connected directly to the camera. But I have not run any metrics.

Ron

I connect over WiFi to my Pi. I do have some delay, but I save my actual integration images locally on the Pi and use a USB stick to transfer them off and onto my processing machine, which also runs KStars. I do this because file transfer is very slow over WiFi, so rather than eat into imaging time, I just store locally. Takes me about 10 mins to move the files once I am done, depending on the size of my nights worth of imaging of course.

All of these things to consider. It is what makes it interesting!

Jasem says that he is running a Gigabit LAN. That capability is not available over the standard Ethernet port on the Pi. He probably has a board that plugs into a USB port or perhaps a "hat" that stacks on top of the Pi. Or maybe he means that he has a GigaBit router but connects the Pi over the standard 10/100 port and he relies on INDI buffering the stream. Or perhaps when he streams he has it configured to run at a reduced frame rate. It will be interesting what he says about this.

Thanks for your reply!

Consider another approach - install KStars + Ekos on RPi3 and access it over network with VNC. This way you don't need much network bandwidth because captured images are handled locally.