Ok, after tremendous help and assistance from
I have finally managed to complete the LightSpace calibration of my LG C9 with a cheap meter (i1d3 Retail) and a cheap pattern generator (Raspberry PI).
First of all, I would like to point out I am a newbie who just wanted to get the best out of my tv. So no in depth knowledge nor experience here. I have to admit it took some time and reading to get to the point of basic understanding how the LightSpace software works. My initial impression was that the calibration process with LightSpace would include much more knowledge of the color science and much more manual inputs than the so called auto calibration in Calman, but it turned out to be pretty simple in the end. The software is so powerful and in my case it didn't require a single manual calibration step, as the guidance I received from Ted was just spot on!
The reason I turned to LightSpace and decided to buy the license is my dissatisfaction with Calman autocal. I ran at least 30 separate autocal procedures with different picture presets, and was never really happy with the end result. Each time I used Calman's Lightning LUT as per the official recommendation, however I got better visual results when I first tried the Fixed Grid option. However, after my initial joy (and almost reference level post calibration charts - see my post above), it turned out the LUT had the yellow shark fin, as many other users have reported. The post cal picture had some banding too (can bee checked with Ted's disk files). The yellow spike anomaly could only be seen within the LightSpace cube preview, as the Calman color checker is pretty rudimentary and does not give you the full picture.
To cut the long story short, I needed to make some preparation steps in order to let LightSpace do its magic.
was blazing fast and tireless in guiding me through the learning curve. First I bought a Raspberry PI 3 B+ (around 70 euro) which is the recommended low cost pattern generator. I flashed the SD card in order to turn the Raspberry PI into the so called PGenerator. Then I used the brilliant DeviceControl to set the output of the PGenerator to 1080/24 and RGB full. And that's about everything one needs to do in order to have a great pattern generator with flawless integration with LightSpace (also Calman).
As I don't have the LG service remote at this point in time (ordered one online, still waiting for delivery), Ted advised me to skip the service menu part for now and start with the most accurate 'out of the box' color preset/colorspace, which was ISF Dark/Warm 2 in my case. First I did a factory reset of the TV to get rid of the stored Calman LUT's in all the picture modes. Then I disabled all picture processing enhancements and was ready to proceed.
Within DeviceControl (which connects directly to the TV, the same way Calman connects to the TV) I ticked "enable calibration", selected ISF Dark and reset the 3D Lut. Then I selected gamma 2.2 (has nothing to do with the actual target gamma), and set Contrast at 85 and Brightness at 50. Then I unticked enable calibration and was ready for profiling within LightSpace.
For connection between the PGenerator and my MacBook Pro 16'' (running Windows in bootcamp) I used a LAN cable (direct ethernet connection). The PGenerator was connected to the tv's HDMI input 1.
The display characterization process took around 3 hours (fully automatic with no inputs from the user, except from setting the appropriate options for the pattern generator and the meter prior to the measurements).
When the profiling was done, I opened the "Convert Color Space" window in LightSpace, selected the target colorspace - REC.709 and then selected my profile measurements in order to get the correction file from LS. It literally takes a few seconds to get the correction file which needs to be exported afterwards and uploaded to the TV via DeviceControl.
The end result is brilliant in terms of real content, no banding or artifacts whatsoever, natural skin tones, very smooth color gradation, etc. Absolutely beautiful, and I haven't even done the full recommended procedure with the service menu white balance adjustments. Can't wait for the service remote to redo the calibration.
Many thanks to Ted again, and I highly recommend LightSpace to every home enthusiast.