Tuesday, April 17, 2018

Remote Control of Imaging Laptop

It's still snowing here-15 inches last Saturday and Sunday, 2 to 4 more inches tomorrow. Naturally my thoughts have turned to Summer warmth. And where is the best summer warmth found? The Nebraska star party, of course!

Along with that warmth comes mosquitoes. They start coming out at dusk and can be pests the entire night. Your only options are hope for a good breeze, DEET up, or seek shelter. Breezes are not reliable, and DEET doesn't deter Nebraska mosquitoes from buzzing around your head. So option 3 is the most reliable, but how do you monitor your laptop while you're sitting in a vehicle or tent?

With TeamViewer you say! And you're correct, it's the remote access software of choice for many people in astrophotography. It's easy to use, powerful, and free for personal use. But it does come with one catch. As typically used it requires internet access. What do you do if you don't have that?

Conveniently, TeamViewer does permit a no-internet mode of operation. After you install it on your imaging laptop start the application and go to the menu's Extras / Options  dialog. Under "Network settings" change the Incoming LAN Connections to "accept exclusively," click OK and you're done!

(TeamViewer will now assume you're connecting to a LAN and will use the laptop's assigned IP address as "Your ID" on its main screen. Any other devices on the same router will now be able to connect with your laptop, even if the router isn't on the internet.)

Without the internet you need to set up some form of communication. I tried several methods to control my imaging laptop with my phone or tablet.
  • Use the laptop as an access point, then have the controlling device connect to it. I couldn't get TeamViewer to work with this configuration.
  • Use my tablet as an access point. Unfortunately my particular tablet couldn't do this.
  • Use my phone as an access point. This worked, but turning on the capability required phone service to verify that it was allowed.  Since I don't have service at the Nebraska Star Party, this won't do for now. At other sites with service (like the Iowa Star Party) it may be the best option.
  • Use a wireless router. This works perfectly. You don't need an expensive router for this, but there are a couple of considerations: the wi-fi bands used must be compatible with your devices; It should be reasonably waterproof on top to deal with dew, and you might want to look at the voltage requirement. I settled on the ASUS  RT-N12 ($20 from Amazon) that accepts 12V DC and can be powered directly from my batteries. The ASUS is found to consume a scant 2.3W which means it draws a tiny 0.2A.
The theoretical range of the ASUS is 500m, which would provide this coverage around my usual campsite (atop a very low rise) at NSP [CORRECTION: the red circle denotes a distance of 250m around the campsite, not 500m]:

ASUS Theoretical Range at NSP
Will it really be this good? I hope to do a little survey once I have it set up. if it allows me to see my laptop from Dob Row I'll be really pleased. If not, I'm quite confident it will easily reach my tent (maybe 3 to 5m away) and allow me to sit in mosquito-free comfort while imaging!

No comments:

Post a Comment