I noticed that when I use Flip for Pan and Tilt, the focus point is always slightly shifted compered to the starting position.
For example if I take accurate position but I want turn my fixture in the opposite way, by using flip, it's always a bit moved.
In this case the fixture is Sola Frame 3000 but I had the same problem with Sola Frame 1000.
Why does this happen?
Some fixtures have beams which are asymmetric when they exit the unit. To my knowledge both the SolaFrame 1000 and 3000 have this characteristic.
Unless the fixture profile has accurate tilt ranges for these fixtures, when you flip the resulting position will shift slightly. You can test this by putting a fixture at pan/tilt 0, and then rotating pan through its full range. If you see the beam wobble slightly then that fixture has this characteristic.
ETC are correcting these fixtures gradually in the library, so you may find some where Tilt 0 is not DMX 32768.
Thank you for your help.
Ok, but if I put tilt at 90 degrees and pan at -90 degrees, as a starting position, by adding 360 degrees to the pan value I expect the fixture go to the same point but with pan value at 270 deg, correct?
I tried to do it but also in this case the position is different, about one degree. Could there be a problem with the relationship between DMX vale and Pan range?
(If you're seeing actual different data in the Ion for the unit P/T, ignore this)
From the original photo, could it be the gobo wasn't centred in the beam? try full zoom (small) and iris in for the Centre dot, and then swing the lamp around.
It is also worth looking at the speed the unit moves. Some fixtures have more slack in the belt than others, and when they are moved quickly, or from one direction vs another can result in slightly different positions. Try recording each position and then fade between them rather than snapping using flip, see if that makes a difference. You can also try sending the unit there, then panning further in one direction and sending it back.
All moving lights have some degree of tolerance which varies between models.