Powering a Laptop for Astronomy and Running a CPAP while Camping and doing Astronomy

I wrote in an earlier piece, about a month ago about my Lenovo 100S IdeaPad that I use in the field. I run SkyTools 3 on it to record my observations, to bring up finder charts and to manage my observing that evening. The laptop is a basic laptop with 2GB DDR3L / 32GB eMMC flash memory, and an additional 64gb of micro SD card memory where I store the backups for my SkyTools 3.

Someone, while, several people asked locally how I keep the screen so dark while observing at a dark site. In addition how do I recharge the laptop when in the field. First is how to keep a screen dark. It begins with this LINK to ScopeStuff for their Optically Clear Red Acrylic Sheet 1/8" Thick
Up To 17.5 x 11.5 inches product. I actually get 2 sizes, 11.5"x 8" and 17.5" x 11.5" for both laptops I run in the field. The first image below is from ScopeStuff and shows two different size laptops with these screens attached. The next picture is one of my Levono 100S on my wife's piano bench to her Grand.  You can see that I have not darken the screen on the laptop here, so it would show through . In the pictures from Scopestuff they have darkened their screens.  With a screen darkened it often is not necessary to add the next component, but that is up to you.

The two images above show the Levono 100S in the back of my Outback, hooked up to a power source in the car with SkyTools 3 running in white light, and the bottom one showing it running in Night Mode without any other measures added or the screen darkened.

The next item that I add is Rubylith Red Mask Film that is clear, again from Scopestuff LINK.  Again, I get both sizes here, as I run two different laptops in the field at different locations and sites. You can see those in the picture below:

You can see the rubylith above, two sheets with the edges curled somewhat. It is clear so it is reflecting back into the camera. In the picture below you can see the clear, red, acrylic plastic and the two rubber bands that hold it in place.

Now in terms of power, there are two ways I can charge my laptop. My Outback has 3 power outlets, one in the rear cargo area, one under the armrest where you store items, and one under the a/c or in front of the shifter.  I use the power outlet in the rear compartment to charge. My Outback requires that either the car be running or the key be in the A/C position to allow power to the Outlet.  To assist in getting power I have a 150 Watt Power Inverter from Radioshack that works well for this. Here is what it looks like: 

The green light is a 20 amp 30w fuse to help protect the inverter from overloading and blowing the fuse in the care for this outlet.  It also has a USB if I want to charge offf of that and a 9v charger.  I use the electrical here and plug right in, though I could connect an extension cord to it and run and charge the laptop that way. I just don't do that personally.

I also have a battery jumper with me in case, just in case I drain the main battery. I usually start the car a couple of times during a charge and run the engine for about 10 minutes to let the alternator recharge the car battery.  Haven't had a problem doing this.

The second way is I have two deep cycle batteries used to power carts that I use for power.  One I use when I am camping or sleeping over and it runs my CPAP machine, well the one I now use in the field. I cannot use the humidifier when using the battery, if I want to get more than 1 or 2 nights use with it. By not using the humidifier I can get 4 nights out of the battery. I can also run a O2 Cool portable fan from the battery while I sleep (I like a fan blowing on me when it is warm outside).  Mix that with a spray bottle and a few sprays in the face and you cool right down!

Anyway to make this all work I purchased the following items off of Amazon for about $6 each, except for the not pictured Battery Tender which re-charges the batteries at home off of the outlets or the 100w solar panel that will also in about 2 days re-charge a battery.  I don't use that much, it is more for if the power is out long term and I need to charge the batteries to use my CPAP.

This item below, is a Battery Tender 081-0069-6 Ring Terminal Harness with Black Fused 2-Pin Quick Disconnect Plug.  It connects to the battery and then has (hidden under the cord in the center of the image) a plug that connects to the second image, a NOCO ISCC2 5-Way SAE Adapter Connector.  By plugging in the NOCO I get 4 outlets that I could use to draw power of the battery and recharge IF I want to.

Below is the Battery Tender 081-0069-8 Female Cigarette Adaptor for Quick Disconnect that connects into the NOCO above (that is connected to the battery) and then I have the correct adapter that lets me connect my CPAP to this plug and then my CPAP is powered. I also run one for the O2 COOL 12" fan I run, and then I can also if there is enough charge in the battery, charge my laptop up during the day I usually use the battery I am not using for the CPAP to charge the laptop. Takes about 4 to 5 hours to charge off the battery vs 2 hours or so off the car, but I drain the deep cycle battery here, not the car battery. Just depends if I want to stay in the car, and start her up to charge, sometimes I do run the car when I charge as it seems to charge quicker, or if I am using the other laptop for the next night.  

So here are my poor man videos that I crudely made to give you an idea of controlling light and re-charging a laptop or running a CPAP in the field.  Again for the CPAP you need a deep cycle battery, the cords above and the 9volt power cord male that fits the female Adapter above and fits into the back of your CPAP machine.

The first video is bad, really bad. I did not realize that the camera had turned so the video is mostly sideways. This is focused on the 150 Watt Inverter and using that to power the lap top. The car is running at this time.  Here you go.

The next video improves as I did it the right way and shows the power and the rubylith and red clear acrylic covering for the laptop(s).  

This video shows the clear acrylic covering on the laptop and how I would roughly put the rubylith on using the rubber bands to secure it. 

This next video shows how I use my deep cycle batteries to re-charge the laptop, and run my CPAP machine and my O2 COOL fan that I got from Lowes.  Oh, please no comments on my 51 year old legs . . . . at least I can still sit with my legs crossed over! 

There you have it, basically.  I recharged my batteries today. One was almost dead for 5 days out in the field, camping and running the CPAP and re-charging the laptop twice and running that fan at night and during the day for me. The other battery took about 3 hours to finish the charge.  My main goal in the film above was to show the alternative way I run power, for those that may want to do something similar. Anyway, hopefully that helps!