I think the problem is caused by clipping what is the best way to get an accurate setting for brightness and contrast for the display as using the clipping patterns did not give accurate values.

The issue has been solved I used Ted's calibration disk with ColourSpace and found the warmest colour temperature setting in the TV is broken as it goes cold at that point so the correct setting was the one before and that produced the best looking greys. And then after calibration everything looks excellent. Thank you so much for helping me and thanks for developing a great piece of software.

Ok latest update the problem hasn't gone but it's improved and the reason for the colour temperature change was because I uploaded the bypass LUT.

Setting the TV to its uncalibrated state will indeed change the colour temp, as it sets it to the TV's native colour temp.

Steve

I've just thought about this and I don't think the guide mentions it but what should the colour temperature be set to before uploading the bypass LUT and calibration as it's overwrites the warm 5 colour temperature by default should I set it to the middle value of 0 before I start as it might be causing a mismatch in the TV.

The guide on the website needs to be updated for the procedure for TCL TVs with the new firmware that has a new user interface as that is what is causing confusion and it behaves differently so so what should the gamma be set to the options no longer have 0 is now 1.8 to 2.6 with a new option for BT 1886 plus the colour temperature slider value a reversed I think. I guess I will just have to experiment and let you know.

Thanks

Please check my process and tell me if I'm doing anything wrong.
1 Upload the Bypass LUTs 1D 3D and 3x3 Matrix
2 Set the black level and contrast to prevent clipping, setting the colour saturation and tint controls as well as disabling local dimming.
3 profile the display with greyscale large.
4 generate 1D LUT from that profile and export it as a 1D LUT.
5 Upload 1DLUT to TV.
6 Reprofile with a Cube based profile.
7 Generate 3DLUT from the Cube profile.
8 Export it as 3DLUT then Upload.

Also since the TV has no black level controls I'm using the Ycbcr 444 setting with PGenerator. With ColourSpace set to legal range 8bit.

I just updated the TCL we have here.
The Gamma still has 0 as the default setting, so I'm unable to comment on that.
But the rest of your workflow looks correct, although I would not set the tint/saturation as they will likely be overridden by the LUTs.
You can also skip the 1D LUT, and just focus on the 3D LUT.

Steve

Ok is that equivalent to 2.2 as they renamed them I will give you feedback when I test.

Also I have the model QM8B which is equivalent to C805.

Edit:What model do you have?

We have a C855.

Steve

Ok you should be on firmware V8-0012T01-LF1V509.002303 with the new interface TCL doesn't always update to the latest version I can send a link to you if you would like.

Ok so I've confirmed that uploading any LUT seems to not work properly on this TV it messes with the colour temperature (When I uploaded the unity bypass LUT I made sure colour temperature was on 0 and it repeated it for the +5 setting as well which coincidentally is the closest to target on this TV but it's now become a cooler colour temperature) I've heard that the local dimming function on TCL TVs do alter the colour temperature as part of the algorithm so that would explain why it's not working is there anyway for you to report this bug to TCL as they do not listen to their customers I just wondered if you had a contact with them as you work on their TVs

Edit: do you have to upload the bypass LUT before doing the calibration as you can delete data and picture reset I'm wondering if the bypass LUT could be messing with something although it seems unlikely as the image is fine until local dimming is turned on.

Also the TV I have shares the same firmware as the C855 so if you can update to v509 and test it so we know for sure or can find out if I am doing something wrong.

The TV is on the latest software.
V8-T653T01-LF1V420.

And yes, you need to follow the guides in uploading the bypass LUTs and matrix.

Steve

I did and the latest firmware for your TV is the out of date one provided on the UK TCL network update. You can get V8-0012T01-LF1V509.002303 which is the latest they changed the T653T01 to 0012T01 Recently. 420 still has old interface. But you probably shouldn't try the new firmware as it seems bugged with the LUT files.