O
Olaf Schultz
- Jan 1, 1970
- 0
Moin moin,
I have here:
1. an used Minolta CA100 (not the plus), last calibration 2005
2. a freshly from Gossen calibrated Gossen Colormaster 3F
3. an integrating sphere 30 cm diameter, painted with BaS04 (ODP97)
and a bunch of LEDs (Samsung and Cree) with, more or less, relative
narrow bins...
The first trials with the CA100 and and Samsung leads to some (censored
words)...the CCT of the LED SLHNW531T0S0QRC5 is even visible not
homogenous over the angle of view... after some time (convergting a tube,
paiting it with BaSO4... I found out, that the sensor port of one of mine
already existing integrating spheres was already big enough to fit in the
CA100-head and it has an intro-port of approx 80 mm, so no problem to put
there the LED...ambient light of course shielded.
Now, after new measurements (all at 100mA, suppose no worth to mention
CCT-shift over the current, no big cooling problems (finger tip is
enough)) following data collected:
# Colormaster3F
# CA-100 CA-100 CA-100 CA-100
# T_main T Lv x y
# [K] [K] [cd/m2] [-] [-]
#1 2 3 4 5 6 7
SLHNW531T0S0QRC5 6280 4870 276 0.348 0.348
SLHNW531T0S0QRC5 6280 4770 310 0.351 0.359
XRE-WHT-L1-WG-R2 5340 4660 400 0.358 0.377
XRE-WHT-L1-WG-R2 5290 4670 372 0.356 0.372
XRE-WHT-L1-WG-R2 5340 4640 348 0.359 0.371
XRE-WHT-L1-7C-Q2 2800 2470 356 0.477 0.410
XRE-WHT-L1-7C-Q2 2800 2410 352 0.481 0.410
XRE-WHT-L1-6C-Q2 3210 2840 347 0.445 0.402
XRE-WHT-L1-6C-Q2 3190 2790 334 0.448 0.401
XPG-WHT-L1-1C-R4 6280 5280 401 0.338 0.367
If I plot the x-y data in x-y diagram, together with black-body-curve and
the binning fields of above mentioned LEDs theres a big mismatch.
But even calculating the x-y of the measured temperature with a function
found on wikipedia...both measurements deliver odd, not constant
positions to the binnings... also searching the next temperature on a
given bbc delivers no reliable prediction of mismatch to the given
binnings...
How to trust on these data, establish a correction-factor or any hints.
I know, that the CA100 is outdated. AFAIK it was used for CRT and for
TFTetc. theres the CA100 plus. I was not able to find any manual for the
old CA100, only for the +. But the main advantage of the 100+ should be
USB, head, which deals with more than 1000 cd/m^2...hopefully no change
in colour-sensivity/functionanlity.
No, I'am not earning my money in this field, it's only an expensive
hobbyhorse...
Greetings,
Olaf
I have here:
1. an used Minolta CA100 (not the plus), last calibration 2005
2. a freshly from Gossen calibrated Gossen Colormaster 3F
3. an integrating sphere 30 cm diameter, painted with BaS04 (ODP97)
and a bunch of LEDs (Samsung and Cree) with, more or less, relative
narrow bins...
The first trials with the CA100 and and Samsung leads to some (censored
words)...the CCT of the LED SLHNW531T0S0QRC5 is even visible not
homogenous over the angle of view... after some time (convergting a tube,
paiting it with BaSO4... I found out, that the sensor port of one of mine
already existing integrating spheres was already big enough to fit in the
CA100-head and it has an intro-port of approx 80 mm, so no problem to put
there the LED...ambient light of course shielded.
Now, after new measurements (all at 100mA, suppose no worth to mention
CCT-shift over the current, no big cooling problems (finger tip is
enough)) following data collected:
# Colormaster3F
# CA-100 CA-100 CA-100 CA-100
# T_main T Lv x y
# [K] [K] [cd/m2] [-] [-]
#1 2 3 4 5 6 7
SLHNW531T0S0QRC5 6280 4870 276 0.348 0.348
SLHNW531T0S0QRC5 6280 4770 310 0.351 0.359
XRE-WHT-L1-WG-R2 5340 4660 400 0.358 0.377
XRE-WHT-L1-WG-R2 5290 4670 372 0.356 0.372
XRE-WHT-L1-WG-R2 5340 4640 348 0.359 0.371
XRE-WHT-L1-7C-Q2 2800 2470 356 0.477 0.410
XRE-WHT-L1-7C-Q2 2800 2410 352 0.481 0.410
XRE-WHT-L1-6C-Q2 3210 2840 347 0.445 0.402
XRE-WHT-L1-6C-Q2 3190 2790 334 0.448 0.401
XPG-WHT-L1-1C-R4 6280 5280 401 0.338 0.367
If I plot the x-y data in x-y diagram, together with black-body-curve and
the binning fields of above mentioned LEDs theres a big mismatch.
But even calculating the x-y of the measured temperature with a function
found on wikipedia...both measurements deliver odd, not constant
positions to the binnings... also searching the next temperature on a
given bbc delivers no reliable prediction of mismatch to the given
binnings...
How to trust on these data, establish a correction-factor or any hints.
I know, that the CA100 is outdated. AFAIK it was used for CRT and for
TFTetc. theres the CA100 plus. I was not able to find any manual for the
old CA100, only for the +. But the main advantage of the 100+ should be
USB, head, which deals with more than 1000 cd/m^2...hopefully no change
in colour-sensivity/functionanlity.
No, I'am not earning my money in this field, it's only an expensive
hobbyhorse...
Greetings,
Olaf
