# Use Below Range Color option doesn't seem to respect "below"

**URL:** https://discourse.paraview.org/t/use-below-range-color-option-doesnt-seem-to-respect-below/12746
**Category:** ParaView Support
**Created:** [August 24, 2023, 8:43pm UTC](https://discourse.paraview.org/t/use-below-range-color-option-doesnt-seem-to-respect-below/12746 "2023-08-24T20:43:44Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![GregVernon](https://discourse.paraview.org/user_avatar/discourse.paraview.org/gregvernon/32/1494_2.png) [@GregVernon](https://discourse.paraview.org/u/GregVernon)
#### Post date: [August 24, 2023, 8:43pm UTC](https://discourse.paraview.org/t/use-below-range-color-option-doesnt-seem-to-respect-below/12746/1 "2023-08-24T20:43:44Z")

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See below image. I’m noticing in my datasets that when a value is 0.0, and I have a colorbar range set to `[0.0, <value>]` that the `Use Below Range Color` option is being used for values `equal to or less than` the minimum value, rather than simply `less than`.

 ![image](https://discourse.paraview.org/uploads/default/original/2X/5/576a3ce1bff6f50312b8197a97165060db7d5a7f.png)

A simple way to replicate is to create a `Box` source, add a `Generate Surface Normals` filter, and then specify to use the Above/Below range colors:

 ![image](https://discourse.paraview.org/uploads/default/original/2X/d/d984440f234f520b88819cd8389235216ecaa0f7.jpeg)

Notice how the maximum value (`+1`) is respected (surface is red, not yellow), but the minimum value (`-1`) isn’t (surface is green, not blue). Seems like even if the cause is some floating-point nonsense, rather than a `<=` instead of `<`, that it might make sense to do a tolerant comparison.

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### Author: ![dcthomp](https://discourse.paraview.org/user_avatar/discourse.paraview.org/dcthomp/32/20_2.png) [@dcthomp](https://discourse.paraview.org/u/dcthomp)
#### Post date: [August 25, 2023, 8:50pm UTC](https://discourse.paraview.org/t/use-below-range-color-option-doesnt-seem-to-respect-below/12746/2 "2023-08-25T20:50:17Z")

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Colormaps should really support both open and closed interval endpoints. I agree this is a missing feature; it will take some shader code to correct it.