Using "Fast Mode" for Tonemapping Color Grading component makes LUT results inconsistent. Result with some LUTs is correct, with others not. Disabling "Fast Mode" in script makes the LUT work correctly in all cases.

Repro steps:

1) Open attched project and scene "TestLUT".
2) Notice how the LUT texture is not working correctly
Comparison 1 - Disable Tonemapping Color Grading and enabled LUT Color Correction, notice correct LUT result
Comparison 2 - Apply LUT "LUT_Adjust2", notice correct LUT result
3) Open script "TonemappingColorGrading.cs", go to line 17 and change bool "fastMode" to false.
4) Notice how the LUT texture now works correctly.

Doc - https://docs.google.com/document/d/1hOac507SwRMYkRFcFyelLGKKdo9UHQ0IfJzh8eUr-Oc/edit