There are several types of luts on the market today.
Luts are not magic. I like to think of luts as presets in Lightroom except for video. Luts adjust things like exposure, saturation, and hue.
I primarily color grade with a program called Color Finale in FCPX. It’s an incredibly powerful tool and it prevents me from having to go to a secondary software like Davinci Resolve or Speed Grade–both great color grading options.
Here’s the best way to apply luts.
The first thing you should do to your image is adjust exposure and balance your highlights, midtones, and shadows. Typically if you can correct the white balance, that will be enough.
Once you have the image corrected for exposure and white balance, it’s time to apply a conversion lut. A conversion lut is used to bring flat footage to Rec.709. So only apply a conversion lut if you’re shooting in a flat profile like SLOG3 or S-Gamut3 Cine4. Check out my S-Gamut3 Cine4 conversion lut here.
Next, apply your grading or look lut. These are luts designed to change the look and feel of your footage without having to grade it manually.
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