I have a 995, which is very similar to the 990:
CMG Ultra
CMG Infinity
I selected the manual white balance, and picked the Ultra as the reference, and white balanced to its beam.
Pick the brighter of the two being compared, and get a meter measurement in matrix mode, which should get an exposure such that there's no saturation, and read it off the screen.
Set the camera on manual, and set the shutter speed and aperture to the same value.
Position the lights at 1 foot or whatever you want, and use the manual focus at that distance.
Taking the pictures at this point should give the proper focus, with exposure set to a value that doesn't saturate the sensor and give a misleading appearance, with comparative color temperature-
The differences in brightness are much more visible than looking at it firsthand, because of the tendency of the eye to adapt and equalize the brightness of everything. If I used 1/60th on the Ultra instead of 1/30th, it would appear pretty much the same as the Infinity shot, indicating it's twice the brightness.
DSCN0502.JPG
CAMERA : E995V1.6
METERING : MATRIX
MODE : M
SHUTTER : 1/30sec
APERTURE : F2.6
EXP +/- : 0.0
FOCAL LENGTH : f8.2mm(X1.0)
IMG ADJUST : AUTO
SENSITIVITY : ISO200
WHITEBAL : PRESET
SHARPNESS : HIGH
DATE : 2002.09.06 11:00
QUALITY : FULL NORMAL
SATURATION : +1
FOCUS AREA : CENTER
DSCN0503.JPG
CAMERA : E995V1.6
METERING : MATRIX
MODE : M
SHUTTER : 1/30sec
APERTURE : F2.6
EXP +/- : 0.0
FOCAL LENGTH : f8.2mm(X1.0)
IMG ADJUST : AUTO
SENSITIVITY : ISO200
WHITEBAL : PRESET
SHARPNESS : HIGH
DATE : 2002.09.06 11:01
QUALITY : FULL NORMAL
SATURATION : +1
FOCUS AREA : CENTER