"How Tall"
An easy-to-use tool to calculate the height of an object from a distance
Instructions
Setup:
1. Set the units you want to work with (feet or meters).
2. Set your height in those units.
3. Set or calculate the number of units per step. Measure or use a known distance (maybe a wall, or a certain number of tiles, etc). Walk from start to end of that distance counting your steps (or using the built in counting tool). Use your normal walking gait. "How Tall" will calculate the number of units per step. This number will be used to calculate your walking distance when you are measuring objects.
Use:
1. Stand at the base of the object you wish to measure.
2. Click "distance", and start tapping the button to count your steps as you walk away from the object.
3. Stop when you are far enough away that you can clearly see the top of the object. Generally, the farther away you walk, the more accurate the height measurements.
4. Press "GO" on the measuring screen, and sight along the edge of the iphone at the top of the object you want to measure. "How Tall" will use the angle of the phone to calculate the height of the object. Press "STOP" to freeze the measuring process, and record the value.
5. NOTE: You can also reverse the process - take the angle measurement first, then count your steps towards the object.
Info
The formula used is: height of object = (distance to object) * tan(angle) +(your height)
Credits
"How Tall" was created by David Hoare. You can check out other projects at davidhoare.net