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An Illustrated Guide to

Grassroots Mapping withBalloons and Kites

To learn more, visit http://grassrootsmapping.org

or 2 mylarsleeping bags

One 2 meter-wideweather balloon

1000m 5kg nylon stringfor balloons

30kg+ strengthnylon string forkites

plasticsoda

bottle

digital camera withcontinuous mode +4 gb or largermemory

duct tape,gaffe tape is

best

rubberbandsscissors

80 cubicfeet or 1.5

cu. metersof helium

a large kite -1m2 or more

heavyworkgloves

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Do you want tomake maps? Doyou needsatellite imagesbut can'tafford them? Doyou want to seeyour home fromabove?

Followtheseinstructions and

you can, for aslittle as $100!

This work is licensedunder a CreativeCommons Attribution

ShareAlike 3.0 License.
http://creativecommons.org/licenses/by-sa/3.0/http://creativecommons.org/licenses/by-sa/3.0/http://creativecommons.org/licenses/by-sa/3.0/http://creativecommons.org/licenses/by-sa/3.0/http://creativecommons.org/licenses/by-sa/3.0/http://creativecommons.org/licenses/by-sa/3.0/


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Build a camera capsule

This simple protective cover stops your lens from hitting the ground, andprotects your camera from hitting walls and trees.

Cut a soda bottle inhalf and putthe camera inside the

top with the loopthrough the bottleneck.

Be sure the cameralens is protected evenwhen it's extended!

Use the rest of the bottle tomake 'wings' to stabilize itin the wind. Cut strips andcrease them to keep themstraight.

This will keep your camerafrom spinning, which blursthe photos.

2cm

Fold a 1 meter loop ofstring and tape itfirmly onto your camera.Be sure the tape doesn'tstop the lens fromextending.

Press the tape downhard - its the onlything keeping yourcamera from slippingout of the string at500 meters high!

Choose and prepare your camera

Any digital camera around 2-300 grams that has a 'continuous mode'can work. You can also use a Canon camera with the CHDK to trigger aphoto every 5 seconds.

To fly longer, youmay need a newerbattery, a largermemory card, oryou can set yourcamera to a lowerresolution. A 4 GB

card fills up in about35 minutes.

In 'Continuous Mode' a camera takes a picture

every 1 second if the trigger is held down. Yourdisplay will show how many pictures you can takeon your card.

Decide whether to use a balloon or kite based on local wind conditions.While kites are cheaper, they're harder to fly, and you may have toprepare for both:

Balloons or kites?

Balloons in


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Prepare and fill your balloon

1.5 meter wide weather balloons workbest, but if you can't get one, you canmake one from plastic. You can useseveral giant trash bags, but they won'tstay inflated for more than an hour --mylar or PET plastic is far more airtight.

Where available, mylar sleeping bagscan be taped shut and will stay filled forseveral days, unlike weather balloons.Two of these are enough to lift a typicalcamera.

Set your camera on continuous mode. Wadup a bit of card paper or use a pencileraser to hold down the camera trigger.Use a rubber band to hold it in place andapply pressure. Be sure the button is beingpressed - you may have to double the bandup.

Move the rubber bandto one side untilyou're readyto start.

Test your valve first by letting some

helium out with nothing attached.Then put your balloon on and slowlyinflate it.

Someone should be incharge of not letting the

balloon touch trees,bushes, or the ground.

You can add a second loop or arubber band and hook it on thebottom of the bottle to hold thecamera firmly against the top.

Even better, put thecap on over the stringwhen the camerais snugly in place,trapping the string.

Bounce the cameraon a mattress andbe sure it doesn'tscrape the groundor fall out.

Set up your camera to auto-trigger page 3 of 4


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Always wear heavy glovesto prevent string burns!

Don't fly near power lines orin thunderstorms.

The highest wind is usually around 2pm, and thelowest is at dawn. Bring water andsunscreen if it's hot out, and charge your camerabatteries the night before

Flying your balloon or kite

Let balloons rise asfast as you can.The wind will push

them down as soonas you stop lettingthem rise.

When using kites, be surethere is at least 5kg ofpull, and let out 20 meters ofstring before making aloop and attaching thecamera.

When selecting a placeto fly from, you'll

have to be upwindof the site youwant to map.

When usingballoons, attach the

camera justbelow the balloon.

Windthe string carefully

- don't let it tangle!If it's bad enough

you'll have to throw itout.

A second person justto wind the string

can be very helpful.

Bring a GPS if youhave one, and write

down the latitudeand longitude, or

record a track.

Even a drawing ofyour site, or a photo

of an existing map is

helpful.

Generally, ifyou fly1000 metershigh, yourpictures willshow around1000 meters onthe ground.

A small mapusually takesaround 2hoursto make.

Once the balloonis 500-1500meters high, trywalking aroundto take picturesof a greater area.

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