Hey Guys. I have a question about the ballast factor with F32T8 IS ballasts. Now, F32T8 ballasts can operate F25T8s and F17T8s (all full-wattage lamps here, not ES F25s). Will a 0.88 BF F32T8 ballast be 0.88BF with any lamp or only with an F32T8? Could a T8 IS electronic ballast be NBF for an F32T8 but HBF with a F17T8?

If the lamp has the same arc voltage as another one, the same ballast will always operate them at the same current, so power. So if one is rated for higher wattage than the second, it will yield lower ballast factor for the first one and higher for the second one.

Otherwise it depends, what is the exact ballast characteristic (output current as a function of the arc voltage, so transferred power as a function of the arc voltage)
The ballast may either maintain the arc current regardless of the arc voltage (mainly dimmable ballasts behave that way; they use the arc current as the primary parameter regulated by the control loop) or maintain constant power (more a hypothetical extreme; but I've seen one dimmable ballasts design operating in this regime as well - they regulate on the real power transfer as the primary regulated parameter). Most ballasts would be somewhere between (elliptic or "resistive" load characteristic).

So it may be anything you just mentioned, each ballast type may differ...