What is a LUT ?

LUT imageA LUT (Look Up Table) is basically a table that says, if the input is a particular colour value make the output another colour, in other words it is just a remapping table – for this colour, remap it to that colour.

In many ways it is similar to the profiles or settings which are designed to correct the colours a television or monitor displays but with a major difference, in that rather than being used to correct colour ranges, LUTs  may be used to change tone and colour for artistic effect.

In summary – LUTs can help you with colour grading, but not colour correction.

Generally LUTs may be applied to either colour or mono images, though if one is being applied to a colour image it will probably be necessary to lower the opacity of the LUT layer.

When to use :

As with any other aspect of your post-processing workflow you should use LUTs in a consistent taking care to ensure :

    • Images have been properly exposed.
    • A proper white balance has been set.
    • Other basic adjustments, such as tonal range, levelling, cropping, healing, highlights/shadows adjustments etc have been made.
    • Apply the LUT.
    • Further refine the image by performing locally targeted adjustments, adding a vignette etc.

LUTs have long been established in the film / video industries, in fact the Teal / Orange LUT (which deepens shadows and lifts skin colours) has almost become a cliche.

More detail:

Amateur Photographer – What are LUTs and how do you use them?

Lutify.me – LUTs for photographers

Life After Photoshop – How LUTs work in photo-editing