  We present the results of an on-sky point spread function reconstruction
(PSF-R) experiment for the Gemini North telescope adaptive optics system,
Altair, in the simplest mode, bright on-axis natural guise star. We demonstrate
that our PSF-R method does work for system performance diagnostic but suffers
from hidden telescope and system aberrations that are not accounted for in the
model, making the reconstruction unsuccessful for Altair, for now. We discuss
the probable origin of the discrepancy. In the last section, we propose
alternative PSF-R methods for future multiple natural and laser guide stars
systems.
