Lookup Tables (LUTs) are presets used by the Color Lookup adjustment layer. When you apply this adjustment layer, Photoshop takes the original colors in your photo and remaps them according to which LUT preset you selected. Photoshop comes with a few built-in LUTs but you can add third-party ones such as the LUTs created by Frank (fotofrank).
A Color Look Up Table maps input to output colors. It is very powerful and photoshop allows you to create them once you have adjusted an image with adjustment layers. They can quickly give your images a repeatable unique look.
I created a LUT to remove all colors but Blue. Just two layers and absolutely no masking.
I've managed to confuse myself over LUT's. Photoshop has them, Camera Raw has them, Lightroom has them - but are they the same LUT's that work in all of them because the directions I've seen for loading them seem to vary a bit? Help! I've also seen LUT's and 3D LUT's referred to - are they the same thing? I've been used to using Camera Profiles in LR and Camera Raw and some things I've seen suggest LUT's and Profiles are the same thing but others suggest otherwise. And what's the difference between .xmp and .cube files (and LR also has .dcp and .lcp as import profile options). Looking for a simple explanation if there is one!
Photoshop and elements+ have Color Look adjustment layers that allow you to apply an existing LUT(Look Up Table) file. Photoshop allows you to create a New LUT file from adjustment layers that are applied to an image, include blend modes. You can Export these adjustments to a LUT formatted file - I use ".cube". These cube files are what I have posted a few times. There are multiple file formats that you can select from.
Once you are in Adobe Camera Raw, you can create a new profile, that can be used in both Lightroom and Photoshop, this new profile can contain the ".cube" file as long as you know the secret handshake (hold down the option/alt key when you create the new profile).
The new profile can be used immediately in Photoshop, Lightroom has to be started after it was created for it to appear.
LUTS and camera profiles are not the something and are different file formats. Profiles can only contain a LUT, however they may contain more, remember the secret handshake. Lightroom uses profile not LUTs. If only a ".CUBE" file is put into a profile, depending how you look at, it's the same effect.
LUT created in Photoshop can be used in most programs that allow/accept .CUBE files.
Thanks Frank: I'm doing some more reading and it's starting to come clearer. I started on the Adobe documentation on Advanced Profiles which was probably a mistake but starting to see how LUT's and XMP profiles are related but different. Going to have to use them some more and maybe make some to understand a bit more.
Fujifilm XT-3 mirrorless Nikon D7000 Photoshop Elements many versions Photoshop CC, Lightroom Classic, ON1 Raw