  The InfraRed Imaging Spectrograph (IRIS) is a first-light instrument for the
Thirty Meter Telescope (TMT) that will be used to sample the corrected adaptive
optics field by the Narrow-Field Infrared Adaptive Optics System (NFIRAOS) with
a near-infrared (0.8 - 2.4 $\mu$m) imaging camera and integral field
spectrograph. To better understand IRIS science specifications we use the IRIS
data simulator to characterize relative photometric precision and accuracy
across the IRIS imaging camera 34"x34" field of view. Because the Point Spread
Function (PSF) varies due to the effects of anisoplanatism, we use the
Anisoplanatic and Instrumental Reconstruction of Off-axis PSFs for AO (AIROPA)
software package to conduct photometric measurements on simulated frames using
PSF-fitting as the PSF varies in single-source, binary, and crowded field use
cases. We report photometric performance of the imaging camera as a function of
the instrumental noise properties including dark current and read noise. Using
the same methods, we conduct comparisons of photometric performance with
reconstructed PSFs, in order to test the veracity of the current
PSF-Reconstruction algorithms for IRIS/TMT.
