understanding *.lut files

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I followed this site to generate a *.lut file: https://www.sidefx.com/docs/hdk/_h_d_k__i_o__l_u_t.html [www.sidefx.com]

The way I understand it is that a number gets mapped to an index: ( (number_in - lut_min) / range_of_lut ) * number_of_entries. The color at that index is then the output.
For a lut with a pre lut, the pre lut is applied first to the color and the output then is treated as the color_in for the 3D lut.

With that in mind I want to create my own LUT for HDR inputs from 0-10 (see below). However when I load it in Nuke or MPlay the colors are much too bright (in nuke it's 10x the input color). Where is my logic wrong?

Version		3
Format		any
Type		3D+1D
From		0.0 10.0
To		0.0 10.0
Black		0.0
White		1.0
Length		3 4
LUT:
Pre {
	0.0	
	3.3333333333333335	
	6.666666666666667	
	10.0	
}
3D {
	0.0 0.0 0.0
	5.0 0.0 0.0
	10.0 0.0 0.0
	0.0 5.0 0.0
	5.0 5.0 0.0
	10.0 5.0 0.0
	0.0 10.0 0.0
	5.0 10.0 0.0
	10.0 10.0 0.0
	0.0 0.0 5.0
	5.0 0.0 5.0
	10.0 0.0 5.0
	0.0 5.0 5.0
	5.0 5.0 5.0
	10.0 5.0 5.0
	0.0 10.0 5.0
	5.0 10.0 5.0
	10.0 10.0 5.0
	0.0 0.0 10.0
	5.0 0.0 10.0
	10.0 0.0 10.0
	0.0 5.0 10.0
	5.0 5.0 10.0
	10.0 5.0 10.0
	0.0 10.0 10.0
	5.0 10.0 10.0
	10.0 10.0 10.0
}
Edited by Marco Dörner - June 30, 2022 06:30:40
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