Jumping mirrors

[triff]

Hello, using a Pearl to control Clay Packy Miniscans, I think this problem is a problem with the light, but I'm ruling out problems at the moment.

When moving the mirror if you move it to its maximum tilt the mirror jumps and it's as though the mirror has physically moved, all the memories are wrong. If you move the mirror to its minimm tilt it jumps and corrects itsself, however I'm sure you can appreciate how annoying this is during a show.
Any ideas?

[Olie]

You are correct this problem is with the light. It normally occurs with old fixtures where the damping of the mirror is not sufficient to maintain the mirror in its position and gravity takes effect. Some fixtures have the capability to adjust the damping to prevent this happening. However I do not think the Miniscan has this.

I suggest you give the light a good clean and service as this might fix the problem.

[mOOse]

This can often also be caused by a break in the tilt motor cable.

The fracture causes a momentary loss of power to one or all of the coils in the stepper causing the motor to momentarily go 'limp'.

To test for this, power up the light, and then move the mirror by hand carefully through the movement of the tilt. If you feel it go limp at any point then the cable will need to be replaced.