Hi. I've had a couple x-rite i1 pros for a while, and have used them
for projector calibration in the past. One is a Rev A with no UV
filter, and the other a Rev D with UV filter.
Currently my interest lies in measuring light sources (LED lights
specifically, CRI, ). The problem is neither of my i1pros have support
for Ambient mode (spotread -v shows this for the revD)
Connecting to the instrument ..
Instrument Type: GretagMacbeth i1 Pro
Serial Number: 713xxx
Firmware version: 506
CPLD version: 999
Date manufactured: 1-9-2011
U.V. filter ?: Yes
Measure Ambient ?: No
Tot. Measurement Count: 59
Remission Spot Count: 22
Remission Scan Count: 38
Date of last Remission spot cal: Mon Mar 26 13:18:02 2012
Remission Spot Count at last cal: 7
Total lamp usage: 303.782654
Init instrument success !
and neither of them came with the ambient filter cap. I'm guessing the
Rev D wasn't ordered with that option, so no cap, and no calibration
in the eeprom. I don't think the Rev A ever supported ambient did it?
My question is, would it be possible to implement a "software
calibration" using a known source (the sun on a clear day, at noon).
Can you capture a spectrum, take the difference from a known spectrum
of the sun on a clear day at noon, and use that in ArgyllCMS as a
calibration file?
Also, this would allow one to build your own ambient filter (is it
just a thin disk of polystyrene plastic?) and calibrate that as well
using the reference source (the sun), wouldn't it?
Does spotread already support this?
Pointing the RevD at some sunlight using emissive mode (it was
partially cloudy during the measurement, but the sun was shining
through the thin cloud, but it wasn't 100% clear, and this is also
taken through a window with unknown coatings), I get some readings
that look reasonable-ish (i think?) but it's displaying the (Caution)
flag! The R9 seems suspiciously low (because of the cloud? the window?
the calibration or lack thereof?)
Result is XYZ: 8536.243377 9047.991940 7000.724118, D50 Lab:
504.765323 -16.228640 18.964222
CCT = 4978K (Duv 0.0072)
Closest Planckian temperature = 4768K (DE2K 9.1)
Closest Daylight temperature = 4868K (DE2K 5.6)
Color Rendering Index (Ra) = 95.2 [ R9 = 83.9 ] (Caution)
R1 = 94.6 R2 = 97.0 R3 = 97.2 R4 = 92.3 R5 = 94.5 R6 =
96.9 R7 = 96.1
R8 = 93.3 R9 = 83.9 R10 = 95.2 R11 = 92.4 R12 = 90.2 R13 =
94.7 R14 = 98.0
Television Lighting Consistency Index 2012 (Qa) = 99.6
IES TM-30-15 Rf = 95.30 Rg = 96.79 CCT = 4978 Duv = 0.005903 (Caution)
ISO Vis, Type 1, Type 2 Density: -0.301030 -0.301030 -0.301030
Status A CMYV Density: -0.301030 -0.301030 -0.301030 -0.301030
Status M CMYV Density: -0.301030 -0.301030 -0.301030 -0.301030
Status T CMYV Density: -0.301030 -0.301030 -0.301030 -0.301030
Status E CMYV Density: -0.301030 -0.301030 -0.301030 -0.301030
