[lug] OT: android elevation app accuracy

[William D. Knoche]

On 09/29/2013 04:48 PM, Bear Giles wrote:
> Actually I just remembered a second approach. If you can run a hose 
> between two buckets of water you can use it as a level. You'll need to 
> make sure that the hose is completely full so the water can freely 
> flow between the buckets but other than that it's a matter of putting 
> the buckets on each corner of the building and figuring out a way to 
> measure the height of the water to what you're trying to check.
An improvement on this technique is to make adapters from hose threads 
to 1/2" barb and a couple pieces of 1/2" clear tubing (4' for each end 
is plenty).
Fill the hose from the faucet with the adapter/tubing on the male end 
and run enough water to  clear the bubbles. Turn off the water and add 
the adapter/tubing to the female end.
You may want to tie wrap the tubing at each end to a rigid stick to make 
it easier to prop up and compare. Measure from the water level up/down 
to the height of the subject. Go to the other and and measure the same 
length to get the target height. Make sure the ends are open and clear 
and wait for the level to settle. You should be able to get 1/16" or 
better accuracy.
I use this often. It is accurate and simple. More accurate than a 
transit far more accurate than a barometric altimeter, much cheaper, 
much easier, direct reading and works around blind corners.
I got rid of my expensive laser level because it was far less accurate 
than this simple method.

>
> On Sun, Sep 29, 2013 at 4:40 PM, Bear Giles <bgiles at coyotesong.com 
> <mailto:bgiles at coyotesong.com>> wrote:
>
>     This reminds me of the old physics major joke about how you
>     determine the height of a skyscraper with a barometer.
>
>     A: find the building super and tell him you have a neat barometer
>     for him if he tells you the height of the building.
>
>     You'll need a level. A barometer isn't going to cut it, not even
>     remotely.
>
>
>     On Sun, Sep 29, 2013 at 4:35 PM, Jed S. Baer <blug at jbaer.cotse.net
>     <mailto:blug at jbaer.cotse.net>> wrote:
>
>         On Sun, 29 Sep 2013 16:28:03 -0600
>         Jed S. Baer wrote:
>
>         > > i.e. how much slope there is, if any,
>         > > between these two corners
>         >
>         > I think your best bet will be to use a string level. Or, a 4
>         foot or
>         > longer beam level, working along your gutter.
>
>         Or,
>         http://www.homedepot.com/p/Johnson-Hand-Held-Sight-Level-80-5556/202911589
>         http://www.homedepot.com/p/Johnson-Torpedo-Laser-Level-40-0915/202258085
>
>         Might be you know someone who has a laser level already?
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