SELF-MADE

Shadow measurement during a sunny day

1. Conditions:
• Sunshine, horizontal base, vertical shadow thrower.
• As a comfortable possibility: the inside-windowsill where in all rule also the edge of the window frame runs in parallel to the position of the sundial-wall and the window panel as a vertical shadow of sun can be used.
  Before with spirit level examine!
  
  2. Working steps (Compares foto):
  The work is to be explained with care, because the exactness of the later calculation depends on it!
• Paper long edge in parallel to the sundial wall (mostly it is enough the paper in the window frame to put in) straighten and with adhesive tape fasten.
• Window panel open and turn thus that the shade fells on the paper.
• This shade with two points mark (and the clock time of this moment notice themselves) and afterwards to a straight line to connect and measure the angle.
• Make a good sketch and keep it for later calculation.
  
  
• To the control and to the necessary security the second measurement still is take some time around midday.