pitch instability in pianos humidity effects.

[Ron Nossaman]

>Visual inspection of a piano in an art gallery with 3 zones. Zone one no
>control, Zone two buffer zone--some control, zone three tightly control
>humidity levels.
>
>Piano had been fully serviced to try to improve stability (tapped,
>tightened, coils set, etc.)
>
>There was a correspondence to pitch change vs. humidity levels. The piano
>was moved from zone to zone and was/is a small Korean product (Howard 171
>cm piano). It was equipped with a damppchaser system (pre bottom cover),
>and use of humidity control was sporadic.
>
>After 18 tunings pitch change at A4 was +10 cents and worst note was +39
>with room humidity of 27% (dc *not* in service, and piano in zone 2).

Don,
You lost me. What was the visual inspection, and how does all this indicate 
to you that the pins moved and pulled the piano sharp?

Ron N