This section explains the meaning of the Two Numbers Shape dimensions produced by the calculator, and provides step by step instructions for marking out your shape on site based on these dimensions. When marking out the shape on-site you will need something to mark the key positions in the shape, and to mark the lines of the shape. You can use witches hats, pegs, and/or Landscape chalk and string to do this.

To simplify the marking out of the numbers, they are based on digital clock style numbers made up of horizontal and vertical bars. This means that GroupCalc only needs to calculate the widths of these bars, not complex curves. The cross bars are narrower than the vertical bars to allow for the fact that the crossbar will look thicker due to the height of the people in the photos

NOTE: If you don't want to use this square style of numbers then set the shape to Custom then use the Custom Shape Editor to draw the numbers you want (see How to Drawn a Custom Shape

The screen shot above shows the calculated results for a two number shape of "88". As with the Rectangle shape, the dimensions of the outer border of the shape area are shown:

  • Width across the front of the shape area - 10.1 metres
  • Width across the back of the shape area - 24.1 metres
  • The distance from the centre of the front row of the shape to the centre of the group is 6.6m
  • The distance from the centre of the back row of the group to the exact centre of the group 15.6
  • The sum of these last two figures gives the total depth of the group 15.6m + 6.6m = 22.2m

In addition to the outer dimensions, GroupCalc calculates the width and height of the horizontal bars that make up the number. It also shows the distance between the bars. The widths of the vertical bars will be larger at the back of the group than the front due to keystone distortion. When viewed from the camera these bars will appear to be the same thickness from front to back. Guide lines are included to assisting in marking out the shape onsite.

Below is a step by step explanation of how to use these measurements to mark out the shape on site.

Step 1: Mark out the location of the camera and the outer border of the shape area

See Keystone Results for an explanation of how to mark out the outer border of the shape area, and the location of the camera. The diagram below shows the results of following this procedure for this example.

Step 2: Mark the segment heights along the centre line of the shape area

GroupCalc divides the height of the numbers into the following segments:

  • the height of the top, middle, and bottom crossbars of the numbers: 5.7m, 2.3m, and 1.3m respectively in this example
  • the height of the gaps between the back and middle crossbars and the middle and front crossbars: 8.7m and 3.8m respectively in this example.

These height measurements are measured at the centre line of the group, not the left or right side.

In this step we mark the height of each these height segment up the centre of the shape as shown in the following diagram.

If you are using GroupCalc Pro, then the heights of the number segments as measured at the edge of the shape are also shown. You can mark these along the edge line of the shape as shown below. This assists in Step 3.

Step 3: Draw the horizontal lines between the height segments 

Now that you have mark the boundaries between the height segments, mark a horizontal line through each mark extending to the edges of the shape area...

Step 4: Mark the segment widths at the front and back of the shape

Next you mark the widths of vertical bars and gaps across the front and back of the shape...

Step 5: Mark the "vertical" lines between the width segments

Now that you have marked the boundaries between the width segments, mark a "vertical" line through each mark extending from the marks on front of the shape area to the corresponding marks at the back of the shape area...

Step 6: Use the horizontal and vertical lines as a guide to draw the numbers

Now that you have the guide lines in place you can use them to draw the outline of the numbers...

 When viewed through the camera the numbers will look square in the frame.