Originally Posted by Jeroen1000
I took reasonable care in matching the FOV between the i1 pro 2 (spectro) and the i1 display pro 3 (colorimeter).
I then took WRGBCMY readings and the profiled meter agreed with the spectro. So I started calibrating, with as only major change after making the profile a different gamma pre-set on the VT60 (2.4 instead of 2.2). I finished calibrating and decided to take new WRGBCMY readings with both spectro and colorimeter. Profile was miles off. I mean differences of 0.01 x,y.
Is it the gamma pre-set or do I have to time everything to allow a certain warm up time for all components? The dE numbers in the screenshot are just the delta between spectro and colorimeter. They do not represent the error compared to the reference.
Also, one thing I notice is that the profiled meter always seems to be off a bit more for red and green. See screenshot
Hi, what software are you using? ... in CalMAN, it has a meter profiling issue which is floating for years, see here: CalMan 5 Release Notes and Discussion
You need multiple verification runs with CalMAN until to get a valid meter correction table, this is why I have design specific meter profiling check layout page.
A lot of users very familiar with the meter profiling procedure are surprised when they perform this test for their first time and found that their created meter correction table is not so accurate...but they haven't realized that can be possible because they were always following the correct procedure but they were missing to check the accuracy of the created meter profile.
Sometimes you will need to re-perform your meter profiling a second time to get a better verification results, with tighter tolerances.
NIST's accepted tolerances are below xy +-0.001 and +-1.5% Luminance.
If you are using CalMAN you can design a workflow layout page like the picture below, of use the Meter Profiling Check Layout Page can be found inside the CalMAN Workflows I send to my calibration disk users.....and it's very useful for users to check if their meter profiling correction table is accurate.
There a lot of times where users are skipping that step and loose a lot of hours later until to realize that the their final result is not so good and they have to re-calibrated from the start because the meter profiling was not good.
About meters warm-up time, just leave their USB plug connected with your notebook for some time before starting measurements. The recommended warm up time is about 20-30 min. The exact time depends from the temperature conditions. It can be longer if the device came from out side in winter time and will be shorter if stored at room temperature.
The meter must be at room temperature, when the meter has stable temperature you will have stable readings over the time, heat is not good for the sensors, when the meter is becoming warm, more noise is added to the sensor. (reducing S/N ratio).
Also, EBU TECH.3325 Publication (Methods for the Measurement of the performance of Studio Monitors) recommends the distance measuring geometry rather than the contact method.