Sounds like the ISF calibration will require the services of an ISF-certified technician. Baka may secret code to access the calibration controls. Once you get into the controls, it seems like you can adjust gray scale, gamma, color space, etc. for individual sources, just like an advanced video processor.
The problem is that I am aware of only one person in the Philippines who is ISF-certified. John from AV Driver - and I don't think they offer Onkyos. They distribute Denons.
Also, even if you can find the codes to unlock the ISF calibration, you will need special equipment (colorimeter) and software to do the calibration.
In other words, I doubt if this feature will be useful for most people in the Philippines.