[sdiy] response shaping circuits for optocouplers?

[Julian]

Hello,

I'm getting sick of not being able to find the exact pot values and response
curves that I want for modifications, and, coupled with this, id also like
to be adding CV controls.

What im thinking is using simple10k lin pots to sweep a voltage between -5
and +5v (ie the same as my CV input) and using this, via some sort of
shaping circuit, to control an optocoupler, something like the H11F1 or
H11F3, or even a vactrol?

Is this a sensible idea, or foolish one?

If its sensible, im sure it must have been done before, and, in which case,
could anyone point me toward some reading?  Im hoping to get linear and both
log and antilog response curves, and, or course, control the maximum and
minimum resistances across the optocoupler quite closely.

Julian