[Pisces]

Nathaniel B: The scale compression (or expansion) should not have been needed. An order of 10 on each scale should have the same difference in pixel coordinates. Only a horizontal shift of the distance scale would be needed to turn the yards into meters.

By how much? Draw a vertical line between the same mark on the time and speed scale. This crosses at a specific distance. Calculate what this should become: i.e. 10 kts in 10 minutes = 3086.67 meters. (=10min *10kts * 1852m/60 min)

Measure the pixel distance (on the original scan) between 3000m and 30000m.

Then the offset of the 3000m mark w.r.t. the 10kts and 10 minutes marks = ( log_10(3086.666)-log_10(3000) )*pixeldistance. The 3000m mark would come left of the vertical line so shift in the appropriate direction.