These are some results that I posted on the CalMAN forum after some tests of the pattern generator in their latest Beta (build 95) of v3.
This is really more of a test of the video adapter than the pattern generator. The machine is the ASUS A8 notebook running a T7250 core2 duo processor, 2.00ghz, 2 gig ram, vista OS.
These are camparisons between my Accupel HDG-3000 and the nvidia using component output into a Sencore SC3100 scope. The levels were compared on a 100% white full field Y output. Pb and
Pr readings were both about 1 microvolt higher on the nvidia and had similar stability to the Accupel.
Y level black to white
Accupel .713 +.001, -.001 vpp
nVidia .717 +.005, -.002 vpp
Y level black to + sync
Accupel .300 +.002, -.001 vpp
nVidia .304 +.002, -.003 vpp
Y level black to -sync
Accupel .307 +.001, -.001 vpp
nVidia .310 +.005, -.005 vpp
Y level -sync to white
Accupel 1.025 +.001, -.001 vpp
nVidia 1.048 +.003, -.001 vpp
Sync was very similar on both devices, with the nVidia adapter actually a little cleaner on transitions. Both units have a similar very slight overshoot on the Y for the first few lines.
Using the PC, the levels and variability were essentially identical with hard drive activity and without and on battery vs ac adapter.
The big result here is about a 23 millivolt increase in y level from the nvidia adapter relative to the Accupel. The variability in the levels were also greater on the Y than the color difference channels, which were very stable. This could have significant impact on a calibration. Other video cards may behave differently, and there should be no difference on digital outputs. Calibration measures using the DVI output on both the PC and the Accupel are within the variance of my probe (EyeOne Pro).