Possible unwanted behaviour of scale factor?

[Andrew Atkinson]

hi all

Just been processing data for a sump using a distox2 in a waterproof box
(for lack of a better word)

So the box adds a bit on the back which means you have to adjust the
zero, and the water mean that you have to scale the readings by about 0.752

So

*calibrate tape -0.05 0.752

However according to the manual and the quick leg I have checked

(magnetic bearing) = ((reading)-(compass zero err)) * (compass scale factor)

Which I take it is the same for the tape.

Now following survex principles for trying not to amend data before
processing, and as I have measured the zero offset in meters the above
does not work, which leads me to wonder if this is the correct behaviour
for tape.

Anyway something to be thought about

Possible ideas are if not units

real = ( reading - offset) * scale

If units eg *calibrate tape -0.05m 0.752

real = reading * scale - offset

Andrew