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Remote operation of telescope from in the house.

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#26 gmartin02

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Posted 02 October 2014 - 01:14 AM

Any one have a wireless solution for when out on the field and there is no internet... laptop at the scope and the remote one in your vehicle or tent 10' - 30' away... Running Maxim, Stellarium... ccd, guide camera, electronic focus, filter wheel....

 

Thanx!

I think the way to do this would be to set the wireless NICs in the laptops to "ad hoc" mode instead of "infrastructure" mode, and make sure they are both set to the same SSID and channel #.

 

Once you establish the "ad hoc" network, you can do things such as remote control (with a VNC client/server application) and file transfer.

 

P.S. Here is a link that shows pictures of how to do it (on Windows XP): http://www.tp-link.us/article/?id=219


Edited by gmartin02, 02 October 2014 - 01:24 AM.


#27 wrecks

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Posted 02 October 2014 - 04:09 PM

 

Any one have a wireless solution for when out on the field and there is no internet... laptop at the scope and the remote one in your vehicle or tent 10' - 30' away... Running Maxim, Stellarium... ccd, guide camera, electronic focus, filter wheel....

 

Thanx!

I think the way to do this would be to set the wireless NICs in the laptops to "ad hoc" mode instead of "infrastructure" mode, and make sure they are both set to the same SSID and channel #.

 

Once you establish the "ad hoc" network, you can do things such as remote control (with a VNC client/server application) and file transfer.

 

P.S. Here is a link that shows pictures of how to do it (on Windows XP): http://www.tp-link.us/article/?id=219

 

I have been trying out DSLRController with my camera and they have a remote control program that connects the camera to a TP-Link MR3040 (Amazon ~$35).  I figured that it should be able to do more than just control my camera since the underlying device is linux (OpenWRT). I compiled a few utilities for it and created my own firmware. I'm pretty sure I can forward both USB and Serial devices over TCP. The MR3040 already has a WiFi device that can act as an AP. So I think I can control my camera and mount over WiFi. Oh and the MR3040 has a battery and is ultra portable (size of a cell phone). I haven't tried it all set up yet so I can let you know how it goes. My goal is to not have a laptop at the telescope but instead just a small embedded device that I can communicate with over WiFi.



#28 gmartin02

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Posted 03 October 2014 - 02:22 PM

 

 

Any one have a wireless solution for when out on the field and there is no internet... laptop at the scope and the remote one in your vehicle or tent 10' - 30' away... Running Maxim, Stellarium... ccd, guide camera, electronic focus, filter wheel....

 

Thanx!

I think the way to do this would be to set the wireless NICs in the laptops to "ad hoc" mode instead of "infrastructure" mode, and make sure they are both set to the same SSID and channel #.

 

Once you establish the "ad hoc" network, you can do things such as remote control (with a VNC client/server application) and file transfer.

 

P.S. Here is a link that shows pictures of how to do it (on Windows XP): http://www.tp-link.us/article/?id=219

 

I have been trying out DSLRController with my camera and they have a remote control program that connects the camera to a TP-Link MR3040 (Amazon ~$35).  I figured that it should be able to do more than just control my camera since the underlying device is linux (OpenWRT). I compiled a few utilities for it and created my own firmware. I'm pretty sure I can forward both USB and Serial devices over TCP. The MR3040 already has a WiFi device that can act as an AP. So I think I can control my camera and mount over WiFi. Oh and the MR3040 has a battery and is ultra portable (size of a cell phone). I haven't tried it all set up yet so I can let you know how it goes. My goal is to not have a laptop at the telescope but instead just a small embedded device that I can communicate with over WiFi.

 

Hi Jeff,

 

That is a very interesting and creative solution. 

 

One question: Are you also going to use this solution for downloading the pictures from the camera during image capture? If so, I wonder if the MR3040 WiFi link will work OK downloading the large image files to the remote vehicle laptop at the same time that the remote vehicle laptop is sending commands back to the MR3040 for telescope/camera/guiding control (mainly guiding commands at the same time as the image downloads).

 

I have read that WiFi connections tend to have very high latency (180ms+) for the first packet sent in a transmission (and variable latency thereafter), particularly when there is a lot of traffic on the WiFi connection (the image downloads), not to mention a high packet loss on "congested" WiFi networks.

 

I guess there is only one way to find out - experiment :)

 

The reason I ask this is that I have had issues with image downloads interfering with camera/guiding commands even when using a single wired (USB) connection between the telescope/camera/guiding components and the imaging laptop (through a powered USB hub at the scope, and  Keyspan USB-Serial adapter at the scope for scope control).

I don't have this problem with my T2i, but when I started using my 6D I would get crashes in both BackyardEOS and PHD guiding when routing everything through a single USB cable. As soon as I started using a separate USB cable for the camera control to the laptop from the guiding/mount control USB cable, everything now works great with the 6D.

 

Let me know how it works out - again, your idea is a really great one and it will be totally cool if it works like you want it to.



#29 wrecks

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Posted 03 October 2014 - 11:34 PM

 

 

 

Any one have a wireless solution for when out on the field and there is no internet... laptop at the scope and the remote one in your vehicle or tent 10' - 30' away... Running Maxim, Stellarium... ccd, guide camera, electronic focus, filter wheel....

 

Thanx!

I think the way to do this would be to set the wireless NICs in the laptops to "ad hoc" mode instead of "infrastructure" mode, and make sure they are both set to the same SSID and channel #.

 

Once you establish the "ad hoc" network, you can do things such as remote control (with a VNC client/server application) and file transfer.

 

P.S. Here is a link that shows pictures of how to do it (on Windows XP): http://www.tp-link.us/article/?id=219

 

I have been trying out DSLRController with my camera and they have a remote control program that connects the camera to a TP-Link MR3040 (Amazon ~$35).  I figured that it should be able to do more than just control my camera since the underlying device is linux (OpenWRT). I compiled a few utilities for it and created my own firmware. I'm pretty sure I can forward both USB and Serial devices over TCP. The MR3040 already has a WiFi device that can act as an AP. So I think I can control my camera and mount over WiFi. Oh and the MR3040 has a battery and is ultra portable (size of a cell phone). I haven't tried it all set up yet so I can let you know how it goes. My goal is to not have a laptop at the telescope but instead just a small embedded device that I can communicate with over WiFi.

 

Hi Jeff,

 

That is a very interesting and creative solution. 

 

One question: Are you also going to use this solution for downloading the pictures from the camera during image capture? If so, I wonder if the MR3040 WiFi link will work OK downloading the large image files to the remote vehicle laptop at the same time that the remote vehicle laptop is sending commands back to the MR3040 for telescope/camera/guiding control (mainly guiding commands at the same time as the image downloads).

 

I have read that WiFi connections tend to have very high latency (180ms+) for the first packet sent in a transmission (and variable latency thereafter), particularly when there is a lot of traffic on the WiFi connection (the image downloads), not to mention a high packet loss on "congested" WiFi networks.

 

I guess there is only one way to find out - experiment :)

 

The reason I ask this is that I have had issues with image downloads interfering with camera/guiding commands even when using a single wired (USB) connection between the telescope/camera/guiding components and the imaging laptop (through a powered USB hub at the scope, and  Keyspan USB-Serial adapter at the scope for scope control).

I don't have this problem with my T2i, but when I started using my 6D I would get crashes in both BackyardEOS and PHD guiding when routing everything through a single USB cable. As soon as I started using a separate USB cable for the camera control to the laptop from the guiding/mount control USB cable, everything now works great with the 6D.

 

Let me know how it works out - again, your idea is a really great one and it will be totally cool if it works like you want it to.

 

I hadn't thought of that so I'll have to watch out for that. Right now I only transfer images to focus. I haven't integrated as many functions into the process yet. I'm just beginning and finding that there are some people that have automated almost everything, similar to large observatories. I imagine the most critical part would be when you use a guiding camera and need to send signals to adjust the mount while you are continually monitoring the images from the guide scope.



#30 mclewis1

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Posted 04 October 2014 - 09:24 AM

You can certainly intermix various connections (cameras, focuser control, mount control, etc.) on a single USB channel but you are probably better off splitting things up a little bit. I think it helps to sit down and think about the volume of data each connection is going to generate and any power requirements a connected device might require.

 

- Mount control is usually a serial protocol that requires very little USB bandwidth and very little power (it's the USB-RS232 serial adapter that uses a little bit of power). Even continuous autoguider move commands don't keep the USB channel busy at all.

- Focuser control is similar and only occasionally uses any bandwidth at all. The focuser control interface is often powered from the USB channel.

- Camera control, usually also serial connections and use very little bandwidth. Like the mount there will usually also be a USB-RS232 adapter drawing a little bit of power.

- Autoguider cameras, these use more bandwidth and those with higher frame rates and higher resolution sensors being the tougher combination. These cameras often also draw a substantial amount of power from the USB channel. The combination planetary imagers/autoguiders tend to be the higher resolution models with lower sensitivity sensors and probably put the most 

- Video cameras (useful for finders, or in some cases as the primary camera), the higher frame rate (25-30fps) use bandwidth continuously but generally these are not high resolution cameras so the combination isn't too bad. Video cameras are externally powered, but the USB frame grabber used to convert video to USB does draw a little power from the USB channel.

- Imaging cameras, these put real pressure on the bandwidth available but only for very short periods of time (the image download). Power is usually not an issue as they are usually externally powered. Because of the intermittent download it can appear that everything works well on a single channel but only every once and a while you get a "freeze" condition. This can often be caused by the occasional overlap of all the device on a USB channel transmitting together.

 

At the minimum I would consider using two USB 2 channels to separate the two biggest bandwidth users. One with the autoguiding camera and some of the low speed connections (focuser, etc.). The other with the primary imager or video and the mount control. This will also help when you need to troubleshoot problems (being able to swap things between the two channels). You should watch the power requirements if all the devices are USB powered. This is where a powered USB hub can be very useful. If the attached devices are externally powered (or draw minimal power) you can sometimes get away with using an un powered hub. The USB spec says that the maximum power supplied to a channel is 500ma. Some channels (particularly on laptops) can reduce this amount or completely shutdown the power to a channel to conserve battery life. Most of the time this won't affect operations (as the power should be available when the channel is active) but if you have intermittent problems with devices like cameras generating a lot of image noise it would be something to consider. USB channels or ports that are siamesed (mounted together) on a laptop can also sometimes share the 500ma power output. Putting the two USB connections on two separated connectors can help in this situation.

 

Another suggestion that doesn't affect bandwidth and such but will help when troubleshooting is labeling connections and keeping cables and devices on the same ports (unless you are troubleshooting a problem). Intermittent USB problems can be really difficult to find and keeping the connections consistent will really help the process and your sanity.








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