How to desaturate shadows only in Premiere?

As another useful tool, I've created a couple specialized LUTs that I can apply in either the Basic or Creative tab LUT slots. And a couple that I did using a combination of Lumetri and the LUT Buddy effect.

I'm used to doing multiple secondaries and/or Looks in SpeedGrade. As I so often will say warm the middle tones a bit, or shift them somewhere just cause it looks better ... but then want the darker shadows and perhaps the higlights to get back to neutral or slightly desaturated. Stacking multiple Lumetri effects with a "heavy" thing like an HSL on every instance can bog PrPro down a bit.

So with a "clean" clip (no other settings applied at all) I went into the HSL, made a key of shadows with the "solid" part up a quarter of the way, the fall-off set to almost the mid-point, then pulled the saturation down about a third.

Went up to the tab "Lumetri" name, where it's got the three little bars to the right ... right-clicked on those, and from the options selected "Save as .cube", and voila, and named it 1LowSatShadow, saving in the Program Files/Adobe/PremierePro 2017/Lumetri/LUTs/Technical folder. I also copied it to the Creative folder.

Now in either tab, I can go to the drop-down list, and it will be right near the top of the options.

I've created another useful LUT ... and rather unique, I think.

Using a clean clip again, go to the HSL, and using the Saturation key slider solo, set it so the solid bar doesn't go past the left 25%, and the fall-off bar up to about 40%. Click the little box below the H-S-L Key sliders and set it to "Color/gray".

Now ... save as a .cube, and give it a name so that it would be the first LUT in Tech LUTs folder.

When you first bring in a clip, that has perhaps a tricky white-balance, use this in that Input LUT slot in the Basic tab, then as the scopes will only be showing the low-saturated colors which should include most of the black/white/gray values of the scene ... while watching the Vectorscope YUV, adjust the Temp and Tint sliders so whatever concentration of neutrals you have in the scene is centered on the center of the Vectorscope where the two lines cross. Now go back to 'no' LUT, and you should have a pretty decently white-balanced clip.

I've made other useful LUTs that I use either in front of or after Lumetri in the Effects Control panel, that I use LUT Buddy to apply. But that's another little tale of how-to that I'll skip for now.

Neil